diff --git a/.claude/settings.local.json b/.claude/settings.local.json
index f33bcf3..78484fa 100644
--- a/.claude/settings.local.json
+++ b/.claude/settings.local.json
@@ -2,7 +2,8 @@
   "permissions": {
     "allow": [
       "Bash(npm run:*)",
-      "Bash(ls:*)"
+      "Bash(ls:*)",
+      "Bash(npm test:*)"
     ]
   }
 }
diff --git a/CLAUDE.md b/CLAUDE.md
index dd24749..5a69891 100644
--- a/CLAUDE.md
+++ b/CLAUDE.md
@@ -98,6 +98,7 @@ Services throw `AppError` subclasses (`NotFoundError`, `ConflictError`, `Forbidd
 5. **`.lean().exec()`** on all Mongoose read queries
 6. **`householdId` filter** on every domain query — this is the multi-tenancy boundary
 7. **No emojis** — never use emoji characters in source code, UI text, console output, or documentation
+8. **`npx` is banned** — never run `npx` for any reason. Use `npm run <script>` for all test, lint, build, and tool invocations. No exceptions.
 
 ## Testing
 
diff --git a/docs/instructions/testing.md b/docs/instructions/testing.md
index 57a9624..841a961 100644
--- a/docs/instructions/testing.md
+++ b/docs/instructions/testing.md
@@ -497,6 +497,8 @@ Use `/* v8 ignore start */` / `/* v8 ignore stop */` for code that cannot be uni
 
 ## Running Tests
 
+**`npx` is banned. Never use it.** Always use `npm run <script>` to invoke Vitest, Playwright, or any other tool.
+
 ```bash
 # All tests (via turbo)
 npm run test
diff --git a/docs/phases/phase-3-regimens-pill-organizer.md b/docs/phases/phase-3-regimens-pill-organizer.md
index c97d389..be766b2 100644
--- a/docs/phases/phase-3-regimens-pill-organizer.md
+++ b/docs/phases/phase-3-regimens-pill-organizer.md
@@ -1,6 +1,6 @@
-# Phase 3 — Regimens & Pill Organizer
+# Phase 3 — Regimens, Pill Organizer & Cabinet Activity Log
 
-**Goal**: Define daily medication schedules (regimens) and batch-dispense from the medicine cabinet into a pill organizer. This is the core convenience feature: instead of tracking individual pill consumption daily, users fill their organizer for N days in a single action.
+**Goal**: Define daily medication schedules (regimens), batch-dispense from the medicine cabinet into a pill organizer, and track every cabinet mutation in an append-only audit log. The audit log provides the financial foundation for spending projections (Phase 4 enriches with formal price surveillance).
 
 **Depends on**: Phase 0, Phase 1 (medicines), Phase 2 (cabinet)
 
@@ -8,16 +8,123 @@
 
 ## Deliverables
 
-1. `Regimen` MongoDB schema and CRUD API
-2. `OrganizerFill` schema and fill/undo API
-3. Pill organizer fill flow with shortage detection
-4. Burn rate calculation (days until empty per medicine)
-5. Regimen and pill organizer web UI
+1. `CabinetEvent` append-only audit log for all cabinet mutations
+2. `Regimen` MongoDB schema and CRUD API
+3. `OrganizerFill` schema and fill/undo API
+4. Pill organizer fill flow with shortage detection and FEFO allocation
+5. Burn rate calculation with spending projections
+6. Cabinet discard endpoint (zero quantity + soft-delete)
+7. Regimen, pill organizer, and cabinet activity web UI
 
 ---
 
 ## Data Model
 
+### CabinetEvent Schema (new collection, append-only)
+
+Every mutation to a cabinet item is recorded as a `CabinetEvent`. This provides the audit trail, financial history, and data for spending projections.
+
+```typescript
+// packages/shared/src/types/cabinet-event.ts
+export interface CabinetEvent {
+  id: string;
+  householdId: string;
+  userId: string;
+  cabinetItemId: string;
+  medicineId: string;
+  medicineName: string;              // Denormalized
+  eventType: CabinetEventType;
+  quantity: number;                  // Signed: positive=added, negative=removed
+  quantityBefore: number;
+  quantityAfter: number;
+  unitPrice?: number;                // PURCHASED events only
+  totalPrice?: number;
+  currency?: string;
+  storeId?: string;                  // Optional string reference (formal Store entity in Phase 4)
+  storeName?: string;                // Denormalized
+  sourceType: CabinetEventSourceType;
+  sourceId?: string;                 // OrganizerFill ID, etc.
+  reason?: string;                   // User-provided for adjust/discard
+  notes?: string;
+  createdAt: Date;
+}
+
+export enum CabinetEventType {
+  PURCHASED = 'purchased',           // Cabinet item added (via addItem)
+  CONSUMED = 'consumed',             // Deducted by organizer fill
+  ADJUSTED = 'adjusted',             // Manual quantity adjustment
+  DISCARDED = 'discarded',           // Item discarded (zero qty + soft-delete)
+  RESTORED = 'restored',             // Reversed by organizer undo
+  DELETED = 'deleted',               // Soft-deleted from cabinet
+}
+
+export enum CabinetEventSourceType {
+  MANUAL = 'manual',
+  ORGANIZER_FILL = 'organizer_fill',
+  ORGANIZER_UNDO = 'organizer_undo',
+  REFILL_LIST = 'refill_list',       // Phase 4
+}
+
+export interface SpendingSummary {
+  byMedicine: SpendingByMedicine[];
+  byPeriod: SpendingByPeriod[];
+  total: number;
+  currency: string | null;
+}
+
+export interface SpendingByMedicine {
+  medicineId: string;
+  medicineName: string;
+  totalSpent: number;
+  totalQuantity: number;
+  avgUnitPrice: number;
+  purchaseCount: number;
+}
+
+export interface SpendingByPeriod {
+  period: string;
+  totalSpent: number;
+}
+```
+
+#### Event Emission Strategy
+
+| Mutation | Event Type | Source Type |
+|----------|-----------|-------------|
+| `cabinet.addItem()` | PURCHASED | manual |
+| `cabinet.update()` (qty change) | ADJUSTED | manual |
+| `cabinet.adjustQuantity()` | ADJUSTED | manual |
+| `cabinet.discard()` | DISCARDED | manual |
+| `cabinet.delete()` | DELETED | manual |
+| `organizer.fill()` | CONSUMED (per deduction) | organizer_fill |
+| `organizer.undoFill()` | RESTORED (per deduction) | organizer_undo |
+
+Events are logged **after** the primary mutation succeeds (not inside transactions for fill/undo -- events are audit records, not source of truth).
+
+#### MongoDB Indexes
+
+```javascript
+// CabinetEvent
+{ householdId: 1, createdAt: -1 }
+{ householdId: 1, cabinetItemId: 1, createdAt: -1 }
+{ householdId: 1, medicineId: 1, createdAt: -1 }
+{ householdId: 1, eventType: 1, createdAt: -1 }
+```
+
+### CabinetItem Enhancement
+
+Add optional purchase fields to existing `CabinetItem`:
+
+```typescript
+// Added to packages/shared/src/types/cabinet.ts
+purchaseDate?: Date;
+unitPrice?: number;
+totalPrice?: number;
+currency?: string;
+storeId?: string;
+storeName?: string;
+```
+
 ### Regimen Schema
 
 ```typescript
@@ -25,8 +132,8 @@
 export interface Regimen {
   id: string;
   householdId: string;
-  userId: string; // Regimens are per-person
-  name: string; // e.g., "Daily medications", "Morning routine"
+  userId: string;             // Regimens are per-person
+  name: string;               // e.g., "Daily medications", "Morning routine"
   isActive: boolean;
   medications: RegimenMedication[];
   createdBy: string;
@@ -36,26 +143,26 @@ export interface Regimen {
 
 export interface RegimenMedication {
   medicineId: string;
-  medicineName: string; // Denormalized
-  medicineStrength: number; // Denormalized
-  medicineStrengthUnit: StrengthUnit; // Denormalized
-  medicineForm: MedicineForm; // Denormalized
-  dosage: number; // e.g., 2 (pills per dose)
+  medicineName: string;       // Denormalized
+  medicineStrength: number;   // Denormalized
+  medicineStrengthUnit: StrengthUnit;
+  medicineForm: MedicineForm;
+  dosage: number;             // e.g., 2 (pills per dose)
   dosageUnit: DosageUnit;
   frequency: DosageFrequency;
-  customFrequencyPerDay?: number; // When frequency is 'custom'
+  customFrequencyPerDay?: number;
   timeOfDay?: TimeOfDay;
-  instructions?: string; // e.g., "Take with food", "Do not crush"
+  instructions?: string;
 }
 
 export enum DosageFrequency {
-  DAILY = 'daily', // 1x per day
-  TWICE_DAILY = 'twice_daily', // 2x per day
-  THREE_TIMES_DAILY = 'three_times_daily', // 3x per day
-  WEEKLY = 'weekly', // 1x per week
+  DAILY = 'daily',
+  TWICE_DAILY = 'twice_daily',
+  THREE_TIMES_DAILY = 'three_times_daily',
+  WEEKLY = 'weekly',
   EVERY_OTHER_DAY = 'every_other_day',
-  AS_NEEDED = 'as_needed', // Excluded from organizer fill calculations
-  CUSTOM = 'custom', // Uses customFrequencyPerDay
+  AS_NEEDED = 'as_needed',   // Excluded from organizer fill calculations
+  CUSTOM = 'custom',         // Uses customFrequencyPerDay
 }
 
 export enum TimeOfDay {
@@ -75,8 +182,8 @@ export interface OrganizerFill {
   householdId: string;
   userId: string;
   regimenId: string;
-  regimenName: string; // Denormalized
-  numberOfDays: number; // Flexible: 1, 6, 7, 14, etc.
+  regimenName: string;        // Denormalized
+  numberOfDays: number;
   fillDate: Date;
   items: OrganizerFillItem[];
   status: OrganizerFillStatus;
@@ -88,10 +195,10 @@ export interface OrganizerFill {
 export interface OrganizerFillItem {
   medicineId: string;
   medicineName: string;
-  quantityNeeded: number; // Total pills needed for N days
-  quantityTaken: number; // Actual pills taken from cabinet
-  wasShort: boolean; // quantityTaken < quantityNeeded
-  shortage: number; // quantityNeeded - quantityTaken (0 if not short)
+  quantityNeeded: number;
+  quantityTaken: number;
+  wasShort: boolean;
+  shortage: number;
   deductions: OrganizerDeduction[];
 }
 
@@ -101,26 +208,34 @@ export interface OrganizerDeduction {
 }
 
 export enum OrganizerFillStatus {
-  COMPLETED = 'completed', // All medicines fully dispensed
-  PARTIAL = 'partial', // Some medicines were short
-  REVERSED = 'reversed', // Fill was undone
+  COMPLETED = 'completed',
+  PARTIAL = 'partial',
+  REVERSED = 'reversed',
 }
 ```
 
 ### BurnRate (Computed, not stored)
 
 ```typescript
-// Calculated from active regimens + cabinet stock
 export interface BurnRate {
   medicineId: string;
   medicineName: string;
-  dailyConsumption: number; // Total pills per day across all regimens
+  dailyConsumption: number;
   totalInCabinet: number;
-  daysUntilEmpty: number | null; // null if dailyConsumption is 0
+  daysUntilEmpty: number | null;
   earliestExpiry: Date | null;
+  avgUnitPrice: number | null;         // Weighted avg from PURCHASED events
+  projectedDailyCost: number | null;   // avgUnitPrice * dailyConsumption
+  projectedMonthlyCost: number | null; // daily * 30
+  projectedYearlyCost: number | null;  // daily * 365
+  currency: string | null;
 }
 ```
 
+### Discard Behavior
+
+Discarding a cabinet item: zero the quantity **and** soft-delete (`isDeleted=true`). The item disappears from the active cabinet list. A DISCARDED event preserves the audit trail (what was discarded, why, how much).
+
 ### MongoDB Indexes
 
 ```javascript
@@ -138,26 +253,42 @@ export interface BurnRate {
 
 ## API Endpoints
 
-### RegimensModule
+### CabinetEventsModule (new)
 
-| Method | Path                    | Description                          | Auth   |
-| ------ | ----------------------- | ------------------------------------ | ------ |
-| GET    | `/regimens`             | List user's regimens                 | member |
-| GET    | `/regimens/:id`         | Get single regimen                   | member |
-| POST   | `/regimens`             | Create regimen                       | member |
-| PATCH  | `/regimens/:id`         | Update regimen                       | member |
-| DELETE | `/regimens/:id`         | Delete regimen                       | member |
-| GET    | `/regimens/burn-rate`   | Burn rate for all active regimens    | member |
+| Method | Path | Description | Auth |
+|--------|------|-------------|------|
+| GET | `/cabinet-events` | List events (filtered by medicineId, eventType, dateRange) | member |
+| GET | `/cabinet-events/by-item/:cabinetItemId` | Events for a single cabinet item | member |
+| GET | `/cabinet-events/spending-summary` | Aggregated spending per medicine and period | member |
 
-### OrganizerModule
+### CabinetModule (modifications)
 
-| Method | Path                          | Description                                  | Auth   |
-| ------ | ----------------------------- | -------------------------------------------- | ------ |
-| GET    | `/organizer/fills`            | List fill history (paginated)                | member |
-| GET    | `/organizer/fills/:id`        | Get single fill details                      | member |
-| POST   | `/organizer/preview`          | Preview a fill (shows quantities, shortages) | member |
-| POST   | `/organizer/fill`             | Execute a fill (deduct from cabinet)         | member |
-| POST   | `/organizer/fills/:id/undo`   | Reverse a fill (restore cabinet quantities)  | member |
+| Method | Path | Description | Auth |
+|--------|------|-------------|------|
+| POST | `/cabinet/:id/discard` | Zero qty + soft-delete + DISCARDED event. Body: `{ reason, notes? }` | member |
+
+All existing mutation endpoints (`POST /cabinet`, `PATCH /cabinet/:id`, `POST /cabinet/:id/adjust`, `DELETE /cabinet/:id`) now emit CabinetEvents. The `addItem` endpoint accepts optional purchase fields (`unitPrice`, `totalPrice`, `currency`, `storeId`, `storeName`).
+
+### RegimensModule (new)
+
+| Method | Path | Description | Auth |
+|--------|------|-------------|------|
+| GET | `/regimens` | List user's regimens | member |
+| GET | `/regimens/:id` | Get single regimen | member |
+| POST | `/regimens` | Create regimen | member |
+| PATCH | `/regimens/:id` | Update regimen | member |
+| DELETE | `/regimens/:id` | Delete regimen | member |
+| GET | `/regimens/burn-rate` | Burn rate + spending projection | member |
+
+### OrganizerModule (new)
+
+| Method | Path | Description | Auth |
+|--------|------|-------------|------|
+| GET | `/organizer/fills` | List fill history (paginated) | member |
+| GET | `/organizer/fills/:id` | Get single fill details | member |
+| POST | `/organizer/preview` | Preview a fill (shows quantities, shortages) | member |
+| POST | `/organizer/fill` | Execute a fill (deduct from cabinet) | member |
+| POST | `/organizer/fills/:id/undo` | Reverse a fill (restore cabinet quantities) | member |
 
 ### Preview Request/Response
 
@@ -165,7 +296,7 @@ export interface BurnRate {
 // POST /organizer/preview
 interface OrganizerPreviewRequest {
   regimenId: string;
-  numberOfDays: number; // Default: 7
+  numberOfDays: number;
 }
 
 interface OrganizerPreviewResponse {
@@ -180,8 +311,9 @@ interface OrganizerPreviewResponse {
     shortage: number;
     cabinetBreakdown: {
       cabinetItemId: string;
-      expirationDate: Date | null;
+      expirationDate: string | null;
       quantityToTake: number;
+      quantityBefore: number;
     }[];
   }[];
   canFillCompletely: boolean;
@@ -196,33 +328,14 @@ interface OrganizerPreviewResponse {
 interface OrganizerFillRequest {
   regimenId: string;
   numberOfDays: number;
-  allowPartial: boolean; // If false, reject when any medicine is short
+  allowPartial: boolean;
   notes?: string;
 }
 ```
 
 ---
 
-## Tasks
-
-### 3.1 — Shared Types & Validation
-
-- Add regimen types to `packages/shared/src/types/regimen.ts`
-- Add organizer fill types to `packages/shared/src/types/organizer-fill.ts`
-- Zod schemas:
-  - `CreateRegimenSchema`
-  - `UpdateRegimenSchema`
-  - `OrganizerPreviewSchema`
-  - `OrganizerFillSchema`
-
-### 3.2 — Regimen CRUD
-
-- `RegimensRepository` and `RegimensService`
-- Standard CRUD scoped to `householdId` + `userId`
-- On create/update: validate that all `medicineId` references exist in the medicine library
-- Denormalize medicine fields (name, strength, unit, form)
-
-### 3.3 — Frequency Multiplier Logic
+## Frequency Multiplier Logic
 
 ```typescript
 /**
@@ -237,118 +350,131 @@ interface OrganizerFillRequest {
  * custom:            dosage * customFrequencyPerDay * numberOfDays
  */
 function calculateQuantityNeeded(
-  medication: RegimenMedication,
+  dosage: number,
+  frequency: DosageFrequency,
   numberOfDays: number,
+  customFrequencyPerDay?: number,
 ): number;
 ```
 
-### 3.4 — Organizer Fill Service
+Implemented as a pure function in `packages/shared/src/utils/frequency.ts`.
 
-```typescript
-class OrganizerService {
-  /**
-   * Preview: calculate what would happen without deducting.
-   * For each medicine in the regimen:
-   * 1. Calculate quantity needed (via frequency multiplier)
-   * 2. Check cabinet stock (via CabinetService.getAggregateSummary)
-   * 3. Plan FEFO deductions (earliest expiry first)
-   * 4. Flag shortages
-   */
-  preview(householdId: string, regimenId: string, numberOfDays: number): Promise<OrganizerPreviewResponse>;
+---
 
-  /**
-   * Fill: execute the preview plan.
-   * 1. Re-validate stock (may have changed since preview)
-   * 2. If allowPartial=false and any shortage, reject
-   * 3. Call CabinetService.deductStock for each medicine
-   * 4. Create OrganizerFill record
-   * 5. Return fill details
-   */
-  fill(householdId: string, userId: string, request: OrganizerFillRequest): Promise<OrganizerFill>;
+## Spending Projection
 
-  /**
-   * Undo: reverse a fill.
-   * 1. Verify fill is not already reversed
-   * 2. For each deduction, call CabinetService.restoreStock
-   * 3. Mark fill as reversed
-   */
-  undoFill(householdId: string, fillId: string): Promise<OrganizerFill>;
-}
-```
+In `GET /regimens/burn-rate`:
 
-### 3.5 — Burn Rate Calculation
+1. Sum daily consumption per medicine from active regimens
+2. Get cabinet stock per medicine
+3. Query PURCHASED events for weighted average unit price per medicine
+4. `projectedDailyCost = avgUnitPrice * dailyConsumption`
+5. Monthly = daily * 30, yearly = daily * 365
+6. Return `null` for medicines with no purchase price data
 
-```typescript
-class BurnRateService {
-  /**
-   * For each medicine across all active regimens for a user:
-   * 1. Sum daily consumption: dosage * daily_frequency_multiplier
-   * 2. Get total cabinet stock for that medicine
-   * 3. daysUntilEmpty = floor(totalInCabinet / dailyConsumption)
-   * 4. Include earliest expiry date from cabinet
-   *
-   * Note: 'as_needed' frequency is excluded from burn rate.
-   * Note: If multiple users in household have regimens, each sees their own burn rate.
-   */
-  calculateBurnRates(householdId: string, userId: string): Promise<BurnRate[]>;
-}
-```
+---
 
-### 3.6 — Web UI: Regimens
+## Tasks
 
-- `/regimens` page:
-  - List of user's regimens with active/inactive toggle
-  - Each regimen shows: name, medication count, active status
-  - Expand/click to see all medications with dosage details
-- Add/Edit regimen form:
-  - Name, active toggle
-  - Medications list:
-    - Medicine autocomplete (from library)
-    - Dosage (number + unit)
-    - Frequency dropdown
-    - Time of day (optional)
-    - Instructions (optional)
-    - Add/remove medications
+### 3.0 -- Phase 3 Spec Doc
+- Write/update `docs/phases/phase-3-regimens-pill-organizer.md` with revised scope
 
-### 3.7 — Web UI: Pill Organizer
+### 3.1 -- Shared Enums
+- `packages/shared/src/enums/cabinet-event.enums.ts` -- `CabinetEventType`, `CabinetEventSourceType`
+- `packages/shared/src/enums/regimen.enums.ts` -- `DosageFrequency`, `TimeOfDay`, `OrganizerFillStatus`
+- Update barrel, write tests
 
-- `/organizer` page:
-  - **Fill organizer** section:
-    - Select regimen dropdown
-    - Number of days input (default: 7, adjustable)
-    - "Preview" button -> shows:
-      - Per-medicine breakdown: needed vs available
-      - Shortage warnings (highlighted)
-      - Which cabinet items will be drawn from (FEFO order)
-    - "Fill" button -> executes the fill, shows confirmation
-    - Option for partial fill when shortages exist
-  - **Burn rate** section:
-    - Table: medicine name, daily consumption, total in cabinet, days until empty
-    - Color-coded: green (>14 days), yellow (7-14 days), red (<7 days)
-    - Links to refill alerts (Phase 4)
-  - **Fill history** section:
-    - Recent fills with date, regimen, day count, status
-    - Expand to see per-medicine details
-    - "Undo" button on recent fills (with confirmation)
+### 3.2 -- Shared Types
+- `packages/shared/src/types/cabinet-event.ts`
+- `packages/shared/src/types/regimen.ts`
+- `packages/shared/src/types/organizer-fill.ts`
+- `packages/shared/src/types/burn-rate.ts`
+- Modify `packages/shared/src/types/cabinet.ts` -- add purchase fields
+- Update barrel
+
+### 3.3 -- Shared Validation Schemas
+- `packages/shared/src/validation/cabinet-event.schemas.ts`
+- `packages/shared/src/validation/regimen.schemas.ts`
+- `packages/shared/src/validation/organizer.schemas.ts`
+- Modify `packages/shared/src/validation/cabinet.schemas.ts` -- add purchase fields
+- Update barrel, write tests
+
+### 3.4 -- Frequency Multiplier Utility
+- `packages/shared/src/utils/frequency.ts` -- pure functions
+- `packages/shared/src/utils/index.ts` barrel
+- Tests
+
+### 3.5 -- CabinetEvent Schema + Repository + Service + Routes
+- Mongoose schema with indexes
+- Repository with create, find, aggregation methods
+- Service as thin wrapper
+- Routes: list, by-item, spending-summary
+
+### 3.6 -- Modify Cabinet for Events + Discard
+- Add purchase fields to cabinet Mongoose schema
+- Add `discard()` and `findActiveByMedicineForFEFO()` to repository
+- Inject `cabinetEventsService` into `CabinetService`
+- Emit events on all mutations (add, update, adjust, delete, discard)
+- Add `POST /:id/discard` endpoint
+
+### 3.7 -- Regimen Schema + Repository + Service + Routes
+- Mongoose schema with embedded medications
+- Repository with CRUD scoped to householdId + userId
+- Service with CRUD + medicine validation/denormalization + `calculateBurnRates()`
+- Routes for all CRUD + burn-rate endpoint
+
+### 3.8 -- OrganizerFill Schema + Repository + Service + Routes
+- Mongoose schema with embedded items/deductions
+- Repository with CRUD + status update
+- Service with preview (FEFO), fill (transactional), undoFill (transactional)
+- Routes for all 5 endpoints
+
+### 3.9 -- Register in main.ts
+- Add `cabinetEventsRoutes`, `regimensRoutes`, `organizerRoutes`
+
+### 3.10 -- Web UI: Regimens
+- Regimen list/detail views
+- Add/edit regimen forms with medication management
+- Active/inactive toggle
+
+### 3.11 -- Web UI: Pill Organizer
+- Fill flow: regimen select, day count, preview, fill
+- Burn rate table with spending projections
+- Fill history with undo
+
+### 3.12 -- Web UI: Cabinet Activity
+- Timeline of CabinetEvents
+- Filter by medicine, event type, date range
+- Spending summary view
+
+---
+
+## Impact on Phase 4
+
+Phase 4 (Stores, Prices, Refills) scope unchanged -- it still provides:
+- Formal `Store` entity CRUD
+- `MedicinePriceRecord` for price surveillance (observed prices, not just purchases)
+- Refill alerts + lists
+- Spending analytics dashboards (enriched by CabinetEvent PURCHASED data)
+
+The `storeId`/`storeName` on CabinetEvent are optional strings in Phase 3. They reference Store documents once Phase 4 is built.
 
 ---
 
 ## Acceptance Criteria
 
+- [ ] Every cabinet mutation (add, update, adjust, discard, delete, fill, undo) creates a CabinetEvent
+- [ ] Cabinet items can be created with optional purchase price data
+- [ ] Discard zeros quantity, soft-deletes, and logs DISCARDED event
 - [ ] Can create and manage regimens with multiple medications
 - [ ] Frequency multiplier correctly calculates quantities for all frequency types
 - [ ] Preview accurately shows needed quantities and shortages
 - [ ] Fill deducts from cabinet using FEFO (earliest expiry first)
 - [ ] Partial fills work when `allowPartial` is true
 - [ ] Fill is rejected when `allowPartial` is false and any medicine is short
-- [ ] Undo fully restores cabinet quantities
+- [ ] Undo fully restores cabinet quantities and logs RESTORED events
 - [ ] Undo is idempotent (cannot undo an already-reversed fill)
-- [ ] Burn rate correctly accounts for all active regimens
+- [ ] Burn rate correctly accounts for all active regimens with spending projections
 - [ ] `as_needed` frequency is excluded from fill calculations and burn rate
+- [ ] Spending summary aggregates PURCHASED events by medicine and period
 - [ ] All queries scoped to `householdId`; regimens additionally scoped to `userId`
-
----
-
-## Estimated Effort
-
-Medium-large. The fill/undo transactional logic with FEFO, shortage handling, and burn rate calculations are the most complex parts. UI is moderately complex with the preview/fill flow.
diff --git a/packages/api/src/main.ts b/packages/api/src/main.ts
index 56c4a84..27ad80e 100644
--- a/packages/api/src/main.ts
+++ b/packages/api/src/main.ts
@@ -31,6 +31,9 @@ import householdsRoutes from './modules/households/households.routes.js';
 import medicinesRoutes from './modules/medicines/medicines.routes.js';
 import medicineProductsRoutes from './modules/medicine-products/medicine-products.routes.js';
 import cabinetRoutes from './modules/cabinet/cabinet.routes.js';
+import cabinetEventsRoutes from './modules/cabinet-events/cabinet-events.routes.js';
+import regimensRoutes from './modules/regimens/regimens.routes.js';
+import organizerRoutes from './modules/organizer/organizer.routes.js';
 
 export async function buildApp(opts: { logger?: boolean | object } = {}) {
   const app = Fastify({
@@ -103,6 +106,9 @@ export async function buildApp(opts: { logger?: boolean | object } = {}) {
   await app.register(medicinesRoutes);
   await app.register(medicineProductsRoutes);
   await app.register(cabinetRoutes);
+  await app.register(cabinetEventsRoutes);
+  await app.register(regimensRoutes);
+  await app.register(organizerRoutes);
 
   // Global error handler
   app.setErrorHandler((error, request, reply) => {
diff --git a/packages/api/src/modules/cabinet-events/cabinet-events.repository.test.ts b/packages/api/src/modules/cabinet-events/cabinet-events.repository.test.ts
new file mode 100644
index 0000000..4c6ecc0
--- /dev/null
+++ b/packages/api/src/modules/cabinet-events/cabinet-events.repository.test.ts
@@ -0,0 +1,396 @@
+import { describe, it, expect, vi, beforeEach } from 'vitest';
+
+const { mockFind, mockSave, mockInsertMany, mockAggregate } = vi.hoisted(() => ({
+  mockFind: vi.fn(),
+  mockSave: vi.fn(),
+  mockInsertMany: vi.fn(),
+  mockAggregate: vi.fn(),
+}));
+
+vi.mock('../../schemas/cabinet-event.schema.js', () => {
+  const chain = () => ({
+    sort: vi.fn().mockReturnThis(),
+    limit: vi.fn().mockReturnThis(),
+    lean: vi.fn().mockReturnThis(),
+    exec: mockFind,
+  });
+
+  const aggChain = () => ({
+    exec: mockAggregate,
+  });
+
+  class FakeModel {
+    data: unknown;
+    constructor(data: unknown) {
+      this.data = data;
+    }
+    save = mockSave;
+    toObject() {
+      return this.data;
+    }
+    static find = vi.fn(() => chain());
+    static insertMany = mockInsertMany;
+    static aggregate = vi.fn(() => aggChain());
+  }
+
+  return { CabinetEventModel: FakeModel };
+});
+
+import { CabinetEventsRepository } from './cabinet-events.repository.js';
+
+describe(CabinetEventsRepository.name, () => {
+  let repo: CabinetEventsRepository;
+
+  const baseEventData = {
+    householdId: 'hh1',
+    userId: 'user-1',
+    cabinetItemId: 'ci-1',
+    medicineId: 'med-1',
+    medicineName: 'Metformin',
+    eventType: 'purchased' as const,
+    quantity: 10,
+    quantityBefore: 0,
+    quantityAfter: 10,
+    sourceType: 'manual' as const,
+  };
+
+  beforeEach(() => {
+    vi.clearAllMocks();
+    repo = new CabinetEventsRepository();
+  });
+
+  describe('create', () => {
+    it('creates and returns a cabinet event', async () => {
+      mockSave.mockImplementation(function (this: { toObject: () => unknown }) {
+        return Promise.resolve(this);
+      });
+
+      const result = await repo.create(baseEventData);
+
+      expect(result).toEqual(baseEventData);
+      expect(mockSave).toHaveBeenCalled();
+    });
+  });
+
+  describe('createMany', () => {
+    it('inserts multiple events', async () => {
+      const events = [baseEventData, { ...baseEventData, quantity: 5 }];
+      mockInsertMany.mockResolvedValue(events);
+
+      const result = await repo.createMany(events);
+
+      expect(result).toEqual(events);
+      expect(mockInsertMany).toHaveBeenCalledWith(events);
+    });
+  });
+
+  describe('findByHousehold', () => {
+    it('returns paginated events with no filters', async () => {
+      const items = [{ _id: 'ev-1', quantity: 10 }];
+      mockFind.mockResolvedValue(items);
+
+      const result = await repo.findByHousehold('hh1', { limit: 20 });
+
+      expect(result.data).toEqual(items);
+      expect(result.pagination.hasMore).toBe(false);
+    });
+
+    it('handles cursor-based pagination', async () => {
+      const items = [{ _id: 'ev-2', quantity: 5 }];
+      mockFind.mockResolvedValue(items);
+
+      const cursor = Buffer.from('ev-1').toString('base64');
+      const result = await repo.findByHousehold('hh1', { cursor, limit: 20 });
+
+      expect(result.data).toEqual(items);
+      expect(result.pagination.hasMore).toBe(false);
+    });
+
+    it('sets hasMore when more items exist', async () => {
+      const items = Array.from({ length: 3 }, (_, i) => ({ _id: `ev-${i}`, quantity: i }));
+      mockFind.mockResolvedValue(items);
+
+      const result = await repo.findByHousehold('hh1', { limit: 2 });
+
+      expect(result.data).toHaveLength(2);
+      expect(result.pagination.hasMore).toBe(true);
+      expect(result.pagination.cursor).toBeTruthy();
+    });
+
+    it('returns null cursor when no data', async () => {
+      mockFind.mockResolvedValue([]);
+
+      const result = await repo.findByHousehold('hh1', { limit: 20 });
+
+      expect(result.pagination.cursor).toBeNull();
+      expect(result.pagination.hasMore).toBe(false);
+    });
+
+    it('filters by medicineId', async () => {
+      mockFind.mockResolvedValue([]);
+
+      await repo.findByHousehold('hh1', { medicineId: 'med-1', limit: 20 });
+
+      expect(mockFind).toHaveBeenCalled();
+    });
+
+    it('filters by eventType', async () => {
+      mockFind.mockResolvedValue([]);
+
+      await repo.findByHousehold('hh1', { eventType: 'purchased' as never, limit: 20 });
+
+      expect(mockFind).toHaveBeenCalled();
+    });
+
+    it('filters by startDate only', async () => {
+      mockFind.mockResolvedValue([]);
+
+      await repo.findByHousehold('hh1', {
+        startDate: '2024-01-01T00:00:00.000Z',
+        limit: 20,
+      });
+
+      expect(mockFind).toHaveBeenCalled();
+    });
+
+    it('filters by endDate only', async () => {
+      mockFind.mockResolvedValue([]);
+
+      await repo.findByHousehold('hh1', {
+        endDate: '2024-12-31T00:00:00.000Z',
+        limit: 20,
+      });
+
+      expect(mockFind).toHaveBeenCalled();
+    });
+
+    it('filters by both startDate and endDate', async () => {
+      mockFind.mockResolvedValue([]);
+
+      await repo.findByHousehold('hh1', {
+        startDate: '2024-01-01T00:00:00.000Z',
+        endDate: '2024-12-31T00:00:00.000Z',
+        limit: 20,
+      });
+
+      expect(mockFind).toHaveBeenCalled();
+    });
+  });
+
+  describe('findByCabinetItem', () => {
+    it('returns paginated events for a cabinet item', async () => {
+      const items = [{ _id: 'ev-1', cabinetItemId: 'ci-1' }];
+      mockFind.mockResolvedValue(items);
+
+      const result = await repo.findByCabinetItem('hh1', 'ci-1', { limit: 20 });
+
+      expect(result.data).toEqual(items);
+      expect(result.pagination.hasMore).toBe(false);
+    });
+
+    it('handles cursor-based pagination', async () => {
+      const items = [{ _id: 'ev-2' }];
+      mockFind.mockResolvedValue(items);
+
+      const cursor = Buffer.from('ev-1').toString('base64');
+      const result = await repo.findByCabinetItem('hh1', 'ci-1', { cursor, limit: 20 });
+
+      expect(result.data).toEqual(items);
+      expect(result.pagination.hasMore).toBe(false);
+    });
+
+    it('sets hasMore when more items exist', async () => {
+      const items = Array.from({ length: 3 }, (_, i) => ({ _id: `ev-${i}` }));
+      mockFind.mockResolvedValue(items);
+
+      const result = await repo.findByCabinetItem('hh1', 'ci-1', { limit: 2 });
+
+      expect(result.data).toHaveLength(2);
+      expect(result.pagination.hasMore).toBe(true);
+      expect(result.pagination.cursor).toBeTruthy();
+    });
+
+    it('returns null cursor when no data', async () => {
+      mockFind.mockResolvedValue([]);
+
+      const result = await repo.findByCabinetItem('hh1', 'ci-1', { limit: 20 });
+
+      expect(result.pagination.cursor).toBeNull();
+      expect(result.pagination.hasMore).toBe(false);
+    });
+  });
+
+  describe('getSpendingSummary', () => {
+    it('returns spending summary with default month period', async () => {
+      const byMedicine = [
+        {
+          _id: 'med-1',
+          medicineName: 'Metformin',
+          totalSpent: 100,
+          totalQuantity: 10,
+          avgUnitPrice: 10,
+          purchaseCount: 2,
+          currency: 'USD',
+        },
+      ];
+      const byPeriod = [{ _id: '2024-01', totalSpent: 100 }];
+
+      mockAggregate
+        .mockResolvedValueOnce(byMedicine)
+        .mockResolvedValueOnce(byPeriod);
+
+      const result = await repo.getSpendingSummary('hh1', { period: 'month' });
+
+      expect(result.totalSpent).toBe(100);
+      expect(result.currency).toBe('USD');
+      expect(result.byMedicine).toHaveLength(1);
+      expect(result.byMedicine[0].medicineId).toBe('med-1');
+      expect(result.byMedicine[0].medicineName).toBe('Metformin');
+      expect(result.byMedicine[0].totalSpent).toBe(100);
+      expect(result.byMedicine[0].totalQuantity).toBe(10);
+      expect(result.byMedicine[0].avgUnitPrice).toBe(10);
+      expect(result.byMedicine[0].purchaseCount).toBe(2);
+      expect(result.byPeriod).toHaveLength(1);
+      expect(result.byPeriod[0].period).toBe('2024-01');
+      expect(result.byPeriod[0].totalSpent).toBe(100);
+    });
+
+    it('returns null currency when no medicine data', async () => {
+      mockAggregate
+        .mockResolvedValueOnce([])
+        .mockResolvedValueOnce([]);
+
+      const result = await repo.getSpendingSummary('hh1', { period: 'month' });
+
+      expect(result.totalSpent).toBe(0);
+      expect(result.currency).toBeNull();
+      expect(result.byMedicine).toHaveLength(0);
+      expect(result.byPeriod).toHaveLength(0);
+    });
+
+    it('filters by medicineId', async () => {
+      mockAggregate
+        .mockResolvedValueOnce([])
+        .mockResolvedValueOnce([]);
+
+      await repo.getSpendingSummary('hh1', { period: 'month', medicineId: 'med-1' });
+
+      expect(mockAggregate).toHaveBeenCalledTimes(2);
+    });
+
+    it('filters by startDate only', async () => {
+      mockAggregate
+        .mockResolvedValueOnce([])
+        .mockResolvedValueOnce([]);
+
+      await repo.getSpendingSummary('hh1', {
+        period: 'month',
+        startDate: '2024-01-01T00:00:00.000Z',
+      });
+
+      expect(mockAggregate).toHaveBeenCalledTimes(2);
+    });
+
+    it('filters by endDate only', async () => {
+      mockAggregate
+        .mockResolvedValueOnce([])
+        .mockResolvedValueOnce([]);
+
+      await repo.getSpendingSummary('hh1', {
+        period: 'month',
+        endDate: '2024-12-31T00:00:00.000Z',
+      });
+
+      expect(mockAggregate).toHaveBeenCalledTimes(2);
+    });
+
+    it('filters by both startDate and endDate', async () => {
+      mockAggregate
+        .mockResolvedValueOnce([])
+        .mockResolvedValueOnce([]);
+
+      await repo.getSpendingSummary('hh1', {
+        period: 'month',
+        startDate: '2024-01-01T00:00:00.000Z',
+        endDate: '2024-12-31T00:00:00.000Z',
+      });
+
+      expect(mockAggregate).toHaveBeenCalledTimes(2);
+    });
+
+    it('uses quarter date format', async () => {
+      mockAggregate
+        .mockResolvedValueOnce([])
+        .mockResolvedValueOnce([]);
+
+      await repo.getSpendingSummary('hh1', { period: 'quarter' });
+
+      expect(mockAggregate).toHaveBeenCalledTimes(2);
+    });
+
+    it('uses year date format', async () => {
+      mockAggregate
+        .mockResolvedValueOnce([])
+        .mockResolvedValueOnce([]);
+
+      await repo.getSpendingSummary('hh1', { period: 'year' });
+
+      expect(mockAggregate).toHaveBeenCalledTimes(2);
+    });
+
+    it('handles null currency in first medicine entry', async () => {
+      const byMedicine = [
+        {
+          _id: 'med-1',
+          medicineName: 'Metformin',
+          totalSpent: 50,
+          totalQuantity: 5,
+          avgUnitPrice: 10,
+          purchaseCount: 1,
+          currency: null,
+        },
+      ];
+      mockAggregate
+        .mockResolvedValueOnce(byMedicine)
+        .mockResolvedValueOnce([]);
+
+      const result = await repo.getSpendingSummary('hh1', { period: 'month' });
+
+      expect(result.currency).toBeNull();
+    });
+  });
+
+  describe('getAvgUnitPriceByMedicine', () => {
+    it('returns empty map when no medicine ids provided', async () => {
+      const result = await repo.getAvgUnitPriceByMedicine('hh1', []);
+
+      expect(result).toEqual(new Map());
+      expect(mockAggregate).not.toHaveBeenCalled();
+    });
+
+    it('returns map of avg unit prices', async () => {
+      const results = [
+        { _id: 'med-1', avgUnitPrice: 10.5, currency: 'USD', totalSpent: 105, totalQuantity: 10 },
+        { _id: 'med-2', avgUnitPrice: 5.0, currency: 'EUR', totalSpent: 50, totalQuantity: 10 },
+      ];
+      mockAggregate.mockResolvedValue(results);
+
+      const map = await repo.getAvgUnitPriceByMedicine('hh1', ['med-1', 'med-2']);
+
+      expect(map.size).toBe(2);
+      expect(map.get('med-1')).toEqual({ avgUnitPrice: 10.5, currency: 'USD' });
+      expect(map.get('med-2')).toEqual({ avgUnitPrice: 5.0, currency: 'EUR' });
+    });
+
+    it('handles null currency in results', async () => {
+      const results = [
+        { _id: 'med-1', avgUnitPrice: 10, currency: null, totalSpent: 100, totalQuantity: 10 },
+      ];
+      mockAggregate.mockResolvedValue(results);
+
+      const map = await repo.getAvgUnitPriceByMedicine('hh1', ['med-1']);
+
+      expect(map.get('med-1')).toEqual({ avgUnitPrice: 10, currency: null });
+    });
+  });
+});
diff --git a/packages/api/src/modules/cabinet-events/cabinet-events.repository.ts b/packages/api/src/modules/cabinet-events/cabinet-events.repository.ts
new file mode 100644
index 0000000..070f85d
--- /dev/null
+++ b/packages/api/src/modules/cabinet-events/cabinet-events.repository.ts
@@ -0,0 +1,214 @@
+import { CabinetEventModel } from '../../schemas/cabinet-event.schema.js';
+import type {
+  CabinetEventType,
+  CabinetEventSourceType,
+  CabinetEventQueryInput,
+  SpendingSummaryQueryInput,
+} from '@meshitrack/shared';
+
+export interface CreateCabinetEventData {
+  householdId: string;
+  userId: string;
+  cabinetItemId: string;
+  medicineId: string;
+  medicineName: string;
+  eventType: CabinetEventType;
+  quantity: number;
+  quantityBefore: number;
+  quantityAfter: number;
+  unitPrice?: number;
+  totalPrice?: number;
+  currency?: string;
+  storeId?: string;
+  storeName?: string;
+  sourceType: CabinetEventSourceType;
+  sourceId?: string;
+  reason?: string;
+  notes?: string;
+}
+
+export class CabinetEventsRepository {
+  public async create(data: CreateCabinetEventData) {
+    const event = new CabinetEventModel(data);
+    const saved = await event.save();
+    return saved.toObject();
+  }
+
+  public async createMany(events: CreateCabinetEventData[]) {
+    return CabinetEventModel.insertMany(events);
+  }
+
+  public async findByHousehold(householdId: string, query: CabinetEventQueryInput) {
+    const filter: Record<string, unknown> = { householdId };
+
+    if (query.medicineId) filter['medicineId'] = query.medicineId;
+    if (query.eventType) filter['eventType'] = query.eventType;
+    if (query.startDate || query.endDate) {
+      const dateFilter: Record<string, string> = {};
+      if (query.startDate) dateFilter['$gte'] = query.startDate;
+      if (query.endDate) dateFilter['$lte'] = query.endDate;
+      filter['createdAt'] = dateFilter;
+    }
+
+    if (query.cursor) {
+      const id = Buffer.from(query.cursor, 'base64').toString();
+      filter['_id'] = { $lt: id };
+    }
+
+    const limit = query.limit;
+    const items = await CabinetEventModel.find(filter)
+      .sort({ _id: -1 })
+      .limit(limit + 1)
+      .lean()
+      .exec();
+
+    const hasMore = items.length > limit;
+    const data = hasMore ? items.slice(0, limit) : items;
+    const cursor =
+      data.length > 0 ? Buffer.from(data[data.length - 1]._id.toString()).toString('base64') : null;
+
+    return { data, pagination: { cursor: hasMore ? cursor : null, hasMore } };
+  }
+
+  public async findByCabinetItem(
+    householdId: string,
+    cabinetItemId: string,
+    query: { cursor?: string; limit: number },
+  ) {
+    const filter: Record<string, unknown> = { householdId, cabinetItemId };
+
+    if (query.cursor) {
+      const id = Buffer.from(query.cursor, 'base64').toString();
+      filter['_id'] = { $lt: id };
+    }
+
+    const limit = query.limit;
+    const items = await CabinetEventModel.find(filter)
+      .sort({ _id: -1 })
+      .limit(limit + 1)
+      .lean()
+      .exec();
+
+    const hasMore = items.length > limit;
+    const data = hasMore ? items.slice(0, limit) : items;
+    const cursor =
+      data.length > 0 ? Buffer.from(data[data.length - 1]._id.toString()).toString('base64') : null;
+
+    return { data, pagination: { cursor: hasMore ? cursor : null, hasMore } };
+  }
+
+  public async getSpendingSummary(householdId: string, query: SpendingSummaryQueryInput) {
+    const match: Record<string, unknown> = {
+      householdId,
+      eventType: 'purchased',
+      unitPrice: { $ne: null },
+    };
+    if (query.medicineId) match['medicineId'] = query.medicineId;
+    if (query.startDate || query.endDate) {
+      const dateFilter: Record<string, string> = {};
+      if (query.startDate) dateFilter['$gte'] = query.startDate;
+      if (query.endDate) dateFilter['$lte'] = query.endDate;
+      match['createdAt'] = dateFilter;
+    }
+
+    const dateFormat =
+      query.period === 'year' ? '%Y' : query.period === 'quarter' ? '%Y-Q%q' : '%Y-%m';
+
+    const [byMedicine, byPeriod] = await Promise.all([
+      CabinetEventModel.aggregate([
+        { $match: match },
+        {
+          $group: {
+            _id: '$medicineId',
+            medicineName: { $first: '$medicineName' },
+            totalSpent: { $sum: { $multiply: ['$unitPrice', '$quantity'] } },
+            totalQuantity: { $sum: '$quantity' },
+            purchaseCount: { $sum: 1 },
+            currency: { $first: '$currency' },
+          },
+        },
+        {
+          $addFields: {
+            avgUnitPrice: {
+              $cond: [{ $gt: ['$totalQuantity', 0] }, { $divide: ['$totalSpent', '$totalQuantity'] }, 0],
+            },
+          },
+        },
+        { $sort: { totalSpent: -1 } },
+      ]).exec(),
+      CabinetEventModel.aggregate([
+        { $match: match },
+        {
+          $group: {
+            _id: { $dateToString: { format: dateFormat, date: '$createdAt' } },
+            totalSpent: { $sum: { $multiply: ['$unitPrice', '$quantity'] } },
+          },
+        },
+        { $sort: { _id: 1 } },
+      ]).exec(),
+    ]);
+
+    const totalSpent = byMedicine.reduce(
+      (sum: number, m: Record<string, unknown>) => sum + (m.totalSpent as number),
+      0,
+    );
+    const currency =
+      byMedicine.length > 0 ? (byMedicine[0].currency as string | null) ?? null : null;
+
+    return {
+      totalSpent,
+      currency,
+      byMedicine: byMedicine.map((m: Record<string, unknown>) => ({
+        medicineId: m._id as string,
+        medicineName: m.medicineName as string,
+        totalSpent: m.totalSpent as number,
+        totalQuantity: m.totalQuantity as number,
+        avgUnitPrice: m.avgUnitPrice as number,
+        purchaseCount: m.purchaseCount as number,
+      })),
+      byPeriod: byPeriod.map((p: Record<string, unknown>) => ({
+        period: p._id as string,
+        totalSpent: p.totalSpent as number,
+      })),
+    };
+  }
+
+  public async getAvgUnitPriceByMedicine(householdId: string, medicineIds: string[]) {
+    if (medicineIds.length === 0) return new Map<string, { avgUnitPrice: number; currency: string | null }>();
+
+    const results = await CabinetEventModel.aggregate([
+      {
+        $match: {
+          householdId,
+          eventType: 'purchased',
+          medicineId: { $in: medicineIds },
+          unitPrice: { $ne: null },
+        },
+      },
+      {
+        $group: {
+          _id: '$medicineId',
+          totalSpent: { $sum: { $multiply: ['$unitPrice', '$quantity'] } },
+          totalQuantity: { $sum: '$quantity' },
+          currency: { $first: '$currency' },
+        },
+      },
+      {
+        $addFields: {
+          avgUnitPrice: {
+            $cond: [{ $gt: ['$totalQuantity', 0] }, { $divide: ['$totalSpent', '$totalQuantity'] }, 0],
+          },
+        },
+      },
+    ]).exec();
+
+    const map = new Map<string, { avgUnitPrice: number; currency: string | null }>();
+    for (const r of results) {
+      map.set(r._id as string, {
+        avgUnitPrice: r.avgUnitPrice as number,
+        currency: (r.currency as string | null) ?? null,
+      });
+    }
+    return map;
+  }
+}
diff --git a/packages/api/src/modules/cabinet-events/cabinet-events.routes.test.ts b/packages/api/src/modules/cabinet-events/cabinet-events.routes.test.ts
new file mode 100644
index 0000000..0ab0817
--- /dev/null
+++ b/packages/api/src/modules/cabinet-events/cabinet-events.routes.test.ts
@@ -0,0 +1,387 @@
+import { describe, it, expect, vi, beforeEach, afterEach } from 'vitest';
+import Fastify from 'fastify';
+import { fastifyAwilixPlugin } from '@fastify/awilix';
+import { serializerCompiler, validatorCompiler } from 'fastify-type-provider-zod';
+
+vi.mock('jose', () => ({
+  createRemoteJWKSet: vi.fn(() => 'mock-jwks'),
+  jwtVerify: vi.fn().mockResolvedValue({
+    payload: {
+      sub: 'kc-1',
+      email: 'test@example.com',
+      preferred_username: 'testuser',
+      realm_access: { roles: ['member'] },
+      householdIds: ['hh1'],
+    },
+    protectedHeader: { alg: 'RS256' },
+    key: {},
+  }),
+}));
+
+const { mockListEvents, mockGetEventsByItem, mockGetSpendingSummary } = vi.hoisted(() => ({
+  mockListEvents: vi.fn(),
+  mockGetEventsByItem: vi.fn(),
+  mockGetSpendingSummary: vi.fn(),
+}));
+
+vi.mock('./cabinet-events.repository.js', () => ({
+  CabinetEventsRepository: class {
+    create = vi.fn();
+    createMany = vi.fn();
+    findByHousehold = vi.fn();
+    findByCabinetItem = vi.fn();
+    getSpendingSummary = vi.fn();
+    getAvgUnitPriceByMedicine = vi.fn();
+  },
+}));
+
+vi.mock('./cabinet-events.service.js', () => ({
+  CabinetEventsService: class {
+    logEvent = vi.fn();
+    logEvents = vi.fn();
+    listEvents = mockListEvents;
+    getEventsByItem = mockGetEventsByItem;
+    getSpendingSummary = mockGetSpendingSummary;
+    getAvgUnitPrices = vi.fn();
+  },
+}));
+
+vi.mock('../users/users.repository.js', () => ({
+  UsersRepository: class {
+    findByKeycloakId = vi.fn().mockResolvedValue({ householdIds: ['hh1'] });
+    upsertFromToken = vi.fn().mockResolvedValue({ householdIds: ['hh1'] });
+  },
+}));
+
+import authPlugin from '../../plugins/auth.plugin.js';
+import householdPlugin from '../../plugins/household.plugin.js';
+import usersRoutes from '../users/users.routes.js';
+import cabinetEventsRoutes from './cabinet-events.routes.js';
+
+function makeFakeEvent(overrides = {}) {
+  return {
+    _id: 'ev-1',
+    householdId: 'hh1',
+    userId: 'kc-1',
+    cabinetItemId: 'ci-1',
+    medicineId: 'med-1',
+    medicineName: 'Metformin',
+    eventType: 'purchased',
+    quantity: 10,
+    quantityBefore: 0,
+    quantityAfter: 10,
+    sourceType: 'manual',
+    createdAt: '2024-06-01T00:00:00.000Z',
+    ...overrides,
+  };
+}
+
+describe('cabinet-events.routes', () => {
+  let app: Awaited<ReturnType<typeof buildTestApp>>;
+
+  async function buildTestApp() {
+    const instance = Fastify({ logger: false });
+    instance.setValidatorCompiler(validatorCompiler);
+    instance.setSerializerCompiler(serializerCompiler);
+    await instance.register(fastifyAwilixPlugin, {
+      disposeOnClose: true,
+      disposeOnResponse: true,
+      strictBooleanEnforced: true,
+    });
+    await instance.register(authPlugin);
+    await instance.register(householdPlugin);
+    await instance.register(usersRoutes);
+    await instance.register(cabinetEventsRoutes);
+    await instance.ready();
+    return instance;
+  }
+
+  const authHeaders = { authorization: 'Bearer valid-token' };
+
+  beforeEach(async () => {
+    vi.clearAllMocks();
+    app = await buildTestApp();
+  });
+
+  afterEach(async () => {
+    if (app) await app.close();
+  });
+
+  describe('GET /api/v1/households/:householdId/cabinet-events', () => {
+    it('returns paginated event list', async () => {
+      const event = makeFakeEvent();
+      mockListEvents.mockResolvedValue({
+        data: [event],
+        pagination: { cursor: null, hasMore: false },
+      });
+
+      const res = await app.inject({
+        method: 'GET',
+        url: '/api/v1/households/hh1/cabinet-events',
+        headers: authHeaders,
+      });
+
+      expect(res.statusCode).toBe(200);
+      const body = res.json();
+      expect(body.data).toHaveLength(1);
+      expect(body.data[0].medicineName).toBe('Metformin');
+      expect(body.data[0].eventType).toBe('purchased');
+      expect(body.pagination.hasMore).toBe(false);
+    });
+
+    it('handles ObjectId and Date objects in response', async () => {
+      const event = makeFakeEvent({
+        _id: { toString: () => 'ev-obj' },
+        createdAt: { toISOString: () => '2024-01-01T00:00:00.000Z' },
+        unitPrice: 5.5,
+        totalPrice: 55,
+        currency: 'USD',
+        storeId: 'store-1',
+        storeName: 'Pharmacy A',
+        sourceId: 'src-1',
+        reason: 'restocking',
+        notes: 'bulk purchase',
+      });
+      mockListEvents.mockResolvedValue({
+        data: [event],
+        pagination: { cursor: null, hasMore: false },
+      });
+
+      const res = await app.inject({
+        method: 'GET',
+        url: '/api/v1/households/hh1/cabinet-events',
+        headers: authHeaders,
+      });
+
+      expect(res.statusCode).toBe(200);
+      const body = res.json();
+      expect(body.data[0]._id).toBe('ev-obj');
+      expect(body.data[0].createdAt).toBe('2024-01-01T00:00:00.000Z');
+      expect(body.data[0].unitPrice).toBe(5.5);
+      expect(body.data[0].totalPrice).toBe(55);
+      expect(body.data[0].currency).toBe('USD');
+      expect(body.data[0].storeId).toBe('store-1');
+      expect(body.data[0].storeName).toBe('Pharmacy A');
+      expect(body.data[0].sourceId).toBe('src-1');
+      expect(body.data[0].reason).toBe('restocking');
+      expect(body.data[0].notes).toBe('bulk purchase');
+    });
+
+    it('handles Date instances in createdAt', async () => {
+      const event = makeFakeEvent({
+        createdAt: new Date('2024-03-15T12:00:00.000Z'),
+      });
+      mockListEvents.mockResolvedValue({
+        data: [event],
+        pagination: { cursor: null, hasMore: false },
+      });
+
+      const res = await app.inject({
+        method: 'GET',
+        url: '/api/v1/households/hh1/cabinet-events',
+        headers: authHeaders,
+      });
+
+      expect(res.statusCode).toBe(200);
+      const body = res.json();
+      expect(body.data[0].createdAt).toBe('2024-03-15T12:00:00.000Z');
+    });
+
+    it('omits null optional fields from response', async () => {
+      const event = makeFakeEvent({
+        unitPrice: null,
+        totalPrice: null,
+        currency: null,
+        storeId: null,
+        storeName: null,
+        sourceId: null,
+        reason: null,
+        notes: null,
+      });
+      mockListEvents.mockResolvedValue({
+        data: [event],
+        pagination: { cursor: null, hasMore: false },
+      });
+
+      const res = await app.inject({
+        method: 'GET',
+        url: '/api/v1/households/hh1/cabinet-events',
+        headers: authHeaders,
+      });
+
+      expect(res.statusCode).toBe(200);
+      const body = res.json();
+      expect(body.data[0].unitPrice).toBeUndefined();
+      expect(body.data[0].totalPrice).toBeUndefined();
+      expect(body.data[0].currency).toBeUndefined();
+      expect(body.data[0].storeId).toBeUndefined();
+      expect(body.data[0].storeName).toBeUndefined();
+      expect(body.data[0].sourceId).toBeUndefined();
+      expect(body.data[0].reason).toBeUndefined();
+      expect(body.data[0].notes).toBeUndefined();
+    });
+
+    it('passes query parameters to service', async () => {
+      mockListEvents.mockResolvedValue({
+        data: [],
+        pagination: { cursor: null, hasMore: false },
+      });
+
+      const res = await app.inject({
+        method: 'GET',
+        url: '/api/v1/households/hh1/cabinet-events?medicineId=med-1&eventType=purchased&limit=10',
+        headers: authHeaders,
+      });
+
+      expect(res.statusCode).toBe(200);
+      expect(mockListEvents).toHaveBeenCalledWith('hh1', expect.objectContaining({
+        medicineId: 'med-1',
+        eventType: 'purchased',
+        limit: 10,
+      }));
+    });
+  });
+
+  describe('GET /api/v1/households/:householdId/cabinet-events/by-item/:cabinetItemId', () => {
+    it('returns paginated events for a cabinet item', async () => {
+      const event = makeFakeEvent();
+      mockGetEventsByItem.mockResolvedValue({
+        data: [event],
+        pagination: { cursor: null, hasMore: false },
+      });
+
+      const res = await app.inject({
+        method: 'GET',
+        url: '/api/v1/households/hh1/cabinet-events/by-item/ci-1',
+        headers: authHeaders,
+      });
+
+      expect(res.statusCode).toBe(200);
+      const body = res.json();
+      expect(body.data).toHaveLength(1);
+      expect(body.data[0].cabinetItemId).toBe('ci-1');
+      expect(body.pagination.hasMore).toBe(false);
+    });
+
+    it('passes query parameters to service', async () => {
+      mockGetEventsByItem.mockResolvedValue({
+        data: [],
+        pagination: { cursor: null, hasMore: false },
+      });
+
+      const res = await app.inject({
+        method: 'GET',
+        url: '/api/v1/households/hh1/cabinet-events/by-item/ci-1?limit=5&cursor=abc',
+        headers: authHeaders,
+      });
+
+      expect(res.statusCode).toBe(200);
+      expect(mockGetEventsByItem).toHaveBeenCalledWith('hh1', 'ci-1', expect.objectContaining({
+        limit: 5,
+        cursor: 'abc',
+      }));
+    });
+
+    it('handles ObjectId and Date objects in by-item response', async () => {
+      const event = makeFakeEvent({
+        _id: { toString: () => 'ev-obj-2' },
+        createdAt: new Date('2024-05-01T00:00:00.000Z'),
+      });
+      mockGetEventsByItem.mockResolvedValue({
+        data: [event],
+        pagination: { cursor: null, hasMore: false },
+      });
+
+      const res = await app.inject({
+        method: 'GET',
+        url: '/api/v1/households/hh1/cabinet-events/by-item/ci-1',
+        headers: authHeaders,
+      });
+
+      expect(res.statusCode).toBe(200);
+      const body = res.json();
+      expect(body.data[0]._id).toBe('ev-obj-2');
+      expect(body.data[0].createdAt).toBe('2024-05-01T00:00:00.000Z');
+    });
+  });
+
+  describe('GET /api/v1/households/:householdId/cabinet-events/spending-summary', () => {
+    it('returns spending summary', async () => {
+      mockGetSpendingSummary.mockResolvedValue({
+        totalSpent: 250,
+        currency: 'USD',
+        byMedicine: [
+          {
+            medicineId: 'med-1',
+            medicineName: 'Metformin',
+            totalSpent: 250,
+            totalQuantity: 25,
+            avgUnitPrice: 10,
+            purchaseCount: 5,
+          },
+        ],
+        byPeriod: [
+          { period: '2024-01', totalSpent: 100 },
+          { period: '2024-02', totalSpent: 150 },
+        ],
+      });
+
+      const res = await app.inject({
+        method: 'GET',
+        url: '/api/v1/households/hh1/cabinet-events/spending-summary',
+        headers: authHeaders,
+      });
+
+      expect(res.statusCode).toBe(200);
+      const body = res.json();
+      expect(body.totalSpent).toBe(250);
+      expect(body.currency).toBe('USD');
+      expect(body.byMedicine).toHaveLength(1);
+      expect(body.byMedicine[0].medicineId).toBe('med-1');
+      expect(body.byPeriod).toHaveLength(2);
+    });
+
+    it('passes query parameters to service', async () => {
+      mockGetSpendingSummary.mockResolvedValue({
+        totalSpent: 0,
+        currency: null,
+        byMedicine: [],
+        byPeriod: [],
+      });
+
+      const res = await app.inject({
+        method: 'GET',
+        url: '/api/v1/households/hh1/cabinet-events/spending-summary?period=quarter&medicineId=med-1',
+        headers: authHeaders,
+      });
+
+      expect(res.statusCode).toBe(200);
+      expect(mockGetSpendingSummary).toHaveBeenCalledWith('hh1', expect.objectContaining({
+        period: 'quarter',
+        medicineId: 'med-1',
+      }));
+    });
+
+    it('returns empty summary with null currency', async () => {
+      mockGetSpendingSummary.mockResolvedValue({
+        totalSpent: 0,
+        currency: null,
+        byMedicine: [],
+        byPeriod: [],
+      });
+
+      const res = await app.inject({
+        method: 'GET',
+        url: '/api/v1/households/hh1/cabinet-events/spending-summary',
+        headers: authHeaders,
+      });
+
+      expect(res.statusCode).toBe(200);
+      const body = res.json();
+      expect(body.totalSpent).toBe(0);
+      expect(body.currency).toBeNull();
+      expect(body.byMedicine).toHaveLength(0);
+      expect(body.byPeriod).toHaveLength(0);
+    });
+  });
+});
diff --git a/packages/api/src/modules/cabinet-events/cabinet-events.routes.ts b/packages/api/src/modules/cabinet-events/cabinet-events.routes.ts
new file mode 100644
index 0000000..1df2611
--- /dev/null
+++ b/packages/api/src/modules/cabinet-events/cabinet-events.routes.ts
@@ -0,0 +1,157 @@
+import fp from 'fastify-plugin';
+import { asClass, Lifetime } from 'awilix';
+import type { ZodTypeProvider } from 'fastify-type-provider-zod';
+import { z } from 'zod/v4';
+import {
+  CabinetEventQuerySchema,
+  CabinetEventListResponseSchema,
+  SpendingSummaryQuerySchema,
+  SpendingSummaryResponseSchema,
+} from '@meshitrack/shared';
+import { CabinetEventsRepository } from './cabinet-events.repository.js';
+import { CabinetEventsService } from './cabinet-events.service.js';
+
+type AnyCabinetEventDoc = {
+  _id: string | { toString: () => string };
+  householdId: string;
+  userId: string;
+  cabinetItemId: string;
+  medicineId: string;
+  medicineName: string;
+  eventType: string;
+  quantity: number;
+  quantityBefore: number;
+  quantityAfter: number;
+  unitPrice?: number | null;
+  totalPrice?: number | null;
+  currency?: string | null;
+  storeId?: string | null;
+  storeName?: string | null;
+  sourceType: string;
+  sourceId?: string | null;
+  reason?: string | null;
+  notes?: string | null;
+  createdAt: string | Date | { toISOString: () => string };
+};
+
+function toStr(v: string | { toString: () => string }): string {
+  return typeof v === 'string' ? v : v.toString();
+}
+
+function toIso(v: string | Date | { toISOString: () => string }): string {
+  if (typeof v === 'string') return v;
+  if (v instanceof Date) return v.toISOString();
+  return v.toISOString();
+}
+
+function toCabinetEventResponse(doc: AnyCabinetEventDoc) {
+  return {
+    _id: toStr(doc._id),
+    householdId: doc.householdId,
+    userId: doc.userId,
+    cabinetItemId: doc.cabinetItemId,
+    medicineId: doc.medicineId,
+    medicineName: doc.medicineName,
+    eventType: doc.eventType,
+    quantity: doc.quantity,
+    quantityBefore: doc.quantityBefore,
+    quantityAfter: doc.quantityAfter,
+    ...(doc.unitPrice != null ? { unitPrice: doc.unitPrice } : {}),
+    ...(doc.totalPrice != null ? { totalPrice: doc.totalPrice } : {}),
+    ...(doc.currency ? { currency: doc.currency } : {}),
+    ...(doc.storeId ? { storeId: doc.storeId } : {}),
+    ...(doc.storeName ? { storeName: doc.storeName } : {}),
+    sourceType: doc.sourceType,
+    ...(doc.sourceId ? { sourceId: doc.sourceId } : {}),
+    ...(doc.reason ? { reason: doc.reason } : {}),
+    ...(doc.notes ? { notes: doc.notes } : {}),
+    createdAt: toIso(doc.createdAt),
+  };
+}
+
+declare module '@fastify/awilix' {
+  interface Cradle {
+    cabinetEventsRepository: CabinetEventsRepository;
+    cabinetEventsService: CabinetEventsService;
+  }
+}
+
+export default fp(
+  async (fastify) => {
+    fastify.diContainer.register({
+      cabinetEventsRepository: asClass(CabinetEventsRepository, { lifetime: Lifetime.SINGLETON }),
+      cabinetEventsService: asClass(CabinetEventsService, { lifetime: Lifetime.SINGLETON }),
+    });
+
+    const app = fastify.withTypeProvider<ZodTypeProvider>();
+    const householdParams = z.object({ householdId: z.string() });
+
+    // GET /api/v1/households/:householdId/cabinet-events — list events
+    app.route({
+      method: 'GET',
+      url: '/api/v1/households/:householdId/cabinet-events',
+      schema: {
+        params: householdParams,
+        querystring: CabinetEventQuerySchema,
+        response: { 200: CabinetEventListResponseSchema },
+      },
+      handler: async (request, reply) => {
+        const service = fastify.diContainer.resolve('cabinetEventsService');
+        const result = await service.listEvents(request.params.householdId, request.query);
+        return reply.send({
+          data: result.data.map(toCabinetEventResponse),
+          pagination: result.pagination,
+        });
+      },
+    });
+
+    // GET /api/v1/households/:householdId/cabinet-events/by-item/:cabinetItemId — events for one item
+    app.route({
+      method: 'GET',
+      url: '/api/v1/households/:householdId/cabinet-events/by-item/:cabinetItemId',
+      schema: {
+        params: householdParams.extend({ cabinetItemId: z.string() }),
+        querystring: z.object({
+          cursor: z.string().optional(),
+          limit: z.coerce.number().int().min(1).max(100).default(20),
+        }),
+        response: { 200: CabinetEventListResponseSchema },
+      },
+      handler: async (request, reply) => {
+        const service = fastify.diContainer.resolve('cabinetEventsService');
+        const result = await service.getEventsByItem(
+          request.params.householdId,
+          request.params.cabinetItemId,
+          request.query,
+        );
+        return reply.send({
+          data: result.data.map(toCabinetEventResponse),
+          pagination: result.pagination,
+        });
+      },
+    });
+
+    // GET /api/v1/households/:householdId/cabinet-events/spending-summary — spending analytics
+    app.route({
+      method: 'GET',
+      url: '/api/v1/households/:householdId/cabinet-events/spending-summary',
+      schema: {
+        params: householdParams,
+        querystring: SpendingSummaryQuerySchema,
+        response: { 200: SpendingSummaryResponseSchema },
+      },
+      handler: async (request, reply) => {
+        const service = fastify.diContainer.resolve('cabinetEventsService');
+        const summary = await service.getSpendingSummary(
+          request.params.householdId,
+          request.query,
+        );
+        return reply.send(summary);
+      },
+    });
+  },
+  {
+    name: 'cabinet-events-routes',
+    dependencies: ['auth-plugin'],
+  },
+);
diff --git a/packages/api/src/modules/cabinet-events/cabinet-events.service.test.ts b/packages/api/src/modules/cabinet-events/cabinet-events.service.test.ts
new file mode 100644
index 0000000..f4c0123
--- /dev/null
+++ b/packages/api/src/modules/cabinet-events/cabinet-events.service.test.ts
@@ -0,0 +1,142 @@
+import { describe, it, expect, vi, beforeEach } from 'vitest';
+import { CabinetEventsService } from './cabinet-events.service.js';
+
+describe(CabinetEventsService.name, () => {
+  const mockCabinetEventsRepo = {
+    create: vi.fn(),
+    createMany: vi.fn(),
+    findByHousehold: vi.fn(),
+    findByCabinetItem: vi.fn(),
+    getSpendingSummary: vi.fn(),
+    getAvgUnitPriceByMedicine: vi.fn(),
+  };
+
+  let service: CabinetEventsService;
+
+  const baseEventData = {
+    householdId: 'hh1',
+    userId: 'user-1',
+    cabinetItemId: 'ci-1',
+    medicineId: 'med-1',
+    medicineName: 'Metformin',
+    eventType: 'purchased' as const,
+    quantity: 10,
+    quantityBefore: 0,
+    quantityAfter: 10,
+    sourceType: 'manual' as const,
+  };
+
+  beforeEach(() => {
+    vi.clearAllMocks();
+    service = new CabinetEventsService({
+      cabinetEventsRepository: mockCabinetEventsRepo as never,
+    });
+  });
+
+  describe('logEvent', () => {
+    it('delegates to repository create', async () => {
+      const created = { _id: 'ev-1', ...baseEventData };
+      mockCabinetEventsRepo.create.mockResolvedValue(created);
+
+      const result = await service.logEvent(baseEventData);
+
+      expect(result).toEqual(created);
+      expect(mockCabinetEventsRepo.create).toHaveBeenCalledWith(baseEventData);
+    });
+  });
+
+  describe('logEvents', () => {
+    it('delegates to repository createMany', async () => {
+      const events = [baseEventData, { ...baseEventData, quantity: 5 }];
+      const inserted = events.map((e, i) => ({ _id: `ev-${i}`, ...e }));
+      mockCabinetEventsRepo.createMany.mockResolvedValue(inserted);
+
+      const result = await service.logEvents(events);
+
+      expect(result).toEqual(inserted);
+      expect(mockCabinetEventsRepo.createMany).toHaveBeenCalledWith(events);
+    });
+
+    it('returns empty array for empty input without calling repository', async () => {
+      const result = await service.logEvents([]);
+
+      expect(result).toEqual([]);
+      expect(mockCabinetEventsRepo.createMany).not.toHaveBeenCalled();
+    });
+  });
+
+  describe('listEvents', () => {
+    it('delegates to repository findByHousehold', async () => {
+      const expected = {
+        data: [{ _id: 'ev-1' }],
+        pagination: { cursor: null, hasMore: false },
+      };
+      mockCabinetEventsRepo.findByHousehold.mockResolvedValue(expected);
+
+      const query = { limit: 20 };
+      const result = await service.listEvents('hh1', query);
+
+      expect(result).toEqual(expected);
+      expect(mockCabinetEventsRepo.findByHousehold).toHaveBeenCalledWith('hh1', query);
+    });
+  });
+
+  describe('getEventsByItem', () => {
+    it('delegates to repository findByCabinetItem', async () => {
+      const expected = {
+        data: [{ _id: 'ev-1', cabinetItemId: 'ci-1' }],
+        pagination: { cursor: null, hasMore: false },
+      };
+      mockCabinetEventsRepo.findByCabinetItem.mockResolvedValue(expected);
+
+      const query = { limit: 20 };
+      const result = await service.getEventsByItem('hh1', 'ci-1', query);
+
+      expect(result).toEqual(expected);
+      expect(mockCabinetEventsRepo.findByCabinetItem).toHaveBeenCalledWith('hh1', 'ci-1', query);
+    });
+
+    it('passes cursor through to repository', async () => {
+      const expected = {
+        data: [],
+        pagination: { cursor: null, hasMore: false },
+      };
+      mockCabinetEventsRepo.findByCabinetItem.mockResolvedValue(expected);
+
+      const query = { cursor: 'abc123', limit: 10 };
+      await service.getEventsByItem('hh1', 'ci-1', query);
+
+      expect(mockCabinetEventsRepo.findByCabinetItem).toHaveBeenCalledWith('hh1', 'ci-1', query);
+    });
+  });
+
+  describe('getSpendingSummary', () => {
+    it('delegates to repository getSpendingSummary', async () => {
+      const expected = {
+        totalSpent: 100,
+        currency: 'USD',
+        byMedicine: [],
+        byPeriod: [],
+      };
+      mockCabinetEventsRepo.getSpendingSummary.mockResolvedValue(expected);
+
+      const query = { period: 'month' as const };
+      const result = await service.getSpendingSummary('hh1', query);
+
+      expect(result).toEqual(expected);
+      expect(mockCabinetEventsRepo.getSpendingSummary).toHaveBeenCalledWith('hh1', query);
+    });
+  });
+
+  describe('getAvgUnitPrices', () => {
+    it('delegates to repository getAvgUnitPriceByMedicine', async () => {
+      const expected = new Map([['med-1', { avgUnitPrice: 10, currency: 'USD' }]]);
+      mockCabinetEventsRepo.getAvgUnitPriceByMedicine.mockResolvedValue(expected);
+
+      const result = await service.getAvgUnitPrices('hh1', ['med-1']);
+
+      expect(result).toEqual(expected);
+      expect(mockCabinetEventsRepo.getAvgUnitPriceByMedicine).toHaveBeenCalledWith('hh1', ['med-1']);
+    });
+  });
+});
diff --git a/packages/api/src/modules/cabinet-events/cabinet-events.service.ts b/packages/api/src/modules/cabinet-events/cabinet-events.service.ts
new file mode 100644
index 0000000..b14a7a2
--- /dev/null
+++ b/packages/api/src/modules/cabinet-events/cabinet-events.service.ts
@@ -0,0 +1,43 @@
+import type { CabinetEventsRepository, CreateCabinetEventData } from './cabinet-events.repository.js';
+import type { CabinetEventQueryInput, SpendingSummaryQueryInput } from '@meshitrack/shared';
+
+interface Deps {
+  cabinetEventsRepository: CabinetEventsRepository;
+}
+
+export class CabinetEventsService {
+  private readonly cabinetEventsRepository: CabinetEventsRepository;
+
+  public constructor({ cabinetEventsRepository }: Deps) {
+    this.cabinetEventsRepository = cabinetEventsRepository;
+  }
+
+  public async logEvent(data: CreateCabinetEventData) {
+    return this.cabinetEventsRepository.create(data);
+  }
+
+  public async logEvents(events: CreateCabinetEventData[]) {
+    if (events.length === 0) return [];
+    return this.cabinetEventsRepository.createMany(events);
+  }
+
+  public async listEvents(householdId: string, query: CabinetEventQueryInput) {
+    return this.cabinetEventsRepository.findByHousehold(householdId, query);
+  }
+
+  public async getEventsByItem(
+    householdId: string,
+    cabinetItemId: string,
+    query: { cursor?: string; limit: number },
+  ) {
+    return this.cabinetEventsRepository.findByCabinetItem(householdId, cabinetItemId, query);
+  }
+
+  public async getSpendingSummary(householdId: string, query: SpendingSummaryQueryInput) {
+    return this.cabinetEventsRepository.getSpendingSummary(householdId, query);
+  }
+
+  public async getAvgUnitPrices(householdId: string, medicineIds: string[]) {
+    return this.cabinetEventsRepository.getAvgUnitPriceByMedicine(householdId, medicineIds);
+  }
+}
diff --git a/packages/api/src/modules/cabinet/cabinet.repository.test.ts b/packages/api/src/modules/cabinet/cabinet.repository.test.ts
index f6689da..75ee231 100644
--- a/packages/api/src/modules/cabinet/cabinet.repository.test.ts
+++ b/packages/api/src/modules/cabinet/cabinet.repository.test.ts
@@ -251,4 +251,45 @@ describe(CabinetRepository.name, () => {
       expect(result).toEqual(deleted);
     });
   });
+
+  describe('discard', () => {
+    it('zeros quantity, marks depleted and deleted', async () => {
+      const discarded = { _id: 'ci-1', quantity: 0, status: 'depleted', isDeleted: true };
+      mockFindOneAndUpdate.mockResolvedValue(discarded);
+
+      const result = await repo.discard('ci-1', 'hh1');
+
+      expect(result).toEqual(discarded);
+    });
+
+    it('returns null when item not found', async () => {
+      mockFindOneAndUpdate.mockResolvedValue(null);
+
+      const result = await repo.discard('ci-missing', 'hh1');
+
+      expect(result).toBeNull();
+    });
+  });
+
+  describe('findActiveByMedicineForFEFO', () => {
+    it('returns active items sorted by expiration date', async () => {
+      const items = [
+        { _id: 'ci-1', quantity: 10, expirationDate: new Date('2025-06-01') },
+        { _id: 'ci-2', quantity: 20, expirationDate: new Date('2025-12-01') },
+      ];
+      mockFind.mockResolvedValue(items);
+
+      const result = await repo.findActiveByMedicineForFEFO('hh1', 'med-1');
+
+      expect(result).toEqual(items);
+    });
+
+    it('returns empty array when no active items exist', async () => {
+      mockFind.mockResolvedValue([]);
+
+      const result = await repo.findActiveByMedicineForFEFO('hh1', 'med-1');
+
+      expect(result).toHaveLength(0);
+    });
+  });
 });
diff --git a/packages/api/src/modules/cabinet/cabinet.repository.ts b/packages/api/src/modules/cabinet/cabinet.repository.ts
index 0bb5a7e..808b83e 100644
--- a/packages/api/src/modules/cabinet/cabinet.repository.ts
+++ b/packages/api/src/modules/cabinet/cabinet.repository.ts
@@ -141,4 +141,25 @@ export class CabinetRepository {
       { new: true, lean: true },
     ).exec();
   }
+
+  public async discard(id: string, householdId: string) {
+    return CabinetItemModel.findOneAndUpdate(
+      { _id: id, householdId, isDeleted: false },
+      { $set: { quantity: 0, status: 'depleted', isDeleted: true } },
+      { new: true, lean: true },
+    ).exec();
+  }
+
+  public async findActiveByMedicineForFEFO(householdId: string, medicineId: string) {
+    return CabinetItemModel.find({
+      householdId,
+      medicineId,
+      isDeleted: false,
+      status: 'active',
+      quantity: { $gt: 0 },
+    })
+      .sort({ expirationDate: 1, _id: 1 })
+      .lean()
+      .exec();
+  }
 }
diff --git a/packages/api/src/modules/cabinet/cabinet.routes.test.ts b/packages/api/src/modules/cabinet/cabinet.routes.test.ts
index c4f14d3..5eadebb 100644
--- a/packages/api/src/modules/cabinet/cabinet.routes.test.ts
+++ b/packages/api/src/modules/cabinet/cabinet.routes.test.ts
@@ -29,6 +29,8 @@ const {
   mockFindExpiringSoon,
   mockSoftDelete,
   mockCountByMedicineId,
+  mockDiscard,
+  mockFindActiveByMedicineForFEFO,
 } = vi.hoisted(() => ({
   mockFindByHousehold: vi.fn(),
   mockFindById: vi.fn(),
@@ -39,6 +41,8 @@ const {
   mockFindExpiringSoon: vi.fn(),
   mockSoftDelete: vi.fn(),
   mockCountByMedicineId: vi.fn(),
+  mockDiscard: vi.fn(),
+  mockFindActiveByMedicineForFEFO: vi.fn(),
 }));
 
 vi.mock('./cabinet.repository.js', () => ({
@@ -52,6 +56,8 @@ vi.mock('./cabinet.repository.js', () => ({
     findExpiringSoon = mockFindExpiringSoon;
     softDelete = mockSoftDelete;
     countByMedicineId = mockCountByMedicineId;
+    discard = mockDiscard;
+    findActiveByMedicineForFEFO = mockFindActiveByMedicineForFEFO;
   },
 }));
 
@@ -105,6 +111,28 @@ vi.mock('../medicines/medicines.service.js', () => ({
   },
 }));
 
+vi.mock('../cabinet-events/cabinet-events.repository.js', () => ({
+  CabinetEventsRepository: class {
+    create = vi.fn();
+    createMany = vi.fn();
+    findByHousehold = vi.fn();
+    findByCabinetItem = vi.fn();
+    getSpendingSummary = vi.fn();
+    getAvgUnitPriceByMedicine = vi.fn();
+  },
+}));
+
+vi.mock('../cabinet-events/cabinet-events.service.js', () => ({
+  CabinetEventsService: class {
+    logEvent = vi.fn();
+    logEvents = vi.fn();
+    listEvents = vi.fn();
+    getEventsByItem = vi.fn();
+    getSpendingSummary = vi.fn();
+    getAvgUnitPrices = vi.fn();
+  },
+}));
+
 vi.mock('../users/users.repository.js', () => ({
   UsersRepository: class {
     findByKeycloakId = vi.fn().mockResolvedValue({ householdIds: ['hh1'] });
@@ -117,6 +145,7 @@ import householdPlugin from '../../plugins/household.plugin.js';
 import usersRoutes from '../users/users.routes.js';
 import medicinesRoutes from '../medicines/medicines.routes.js';
 import medicineProductsRoutes from '../medicine-products/medicine-products.routes.js';
+import cabinetEventsRoutes from '../cabinet-events/cabinet-events.routes.js';
 import cabinetRoutes from './cabinet.routes.js';
 
 function makeFakeCabinetItem(overrides = {}) {
@@ -155,6 +184,7 @@ describe('cabinet.routes', () => {
     await instance.register(usersRoutes);
     await instance.register(medicinesRoutes);
     await instance.register(medicineProductsRoutes);
+    await instance.register(cabinetEventsRoutes);
     await instance.register(cabinetRoutes);
     await instance.ready();
     return instance;
@@ -242,6 +272,40 @@ describe('cabinet.routes', () => {
       expect(body.data[0].expirationDate).toBe('2026-12-31T00:00:00.000Z');
       expect(body.data[0].createdAt).toBe('2024-01-01T00:00:00.000Z');
     });
+
+    it('includes optional purchase and store fields when present', async () => {
+      const item = makeFakeCabinetItem({
+        concentration: 5.0,
+        concentrationUnit: 'mg/mL',
+        purchaseDate: new Date('2024-03-01T00:00:00.000Z'),
+        unitPrice: 1.5,
+        totalPrice: 45.0,
+        currency: 'USD',
+        storeId: 'store-1',
+        storeName: 'Pharmacy Plus',
+      });
+      mockFindByHousehold.mockResolvedValue({
+        data: [item],
+        pagination: { cursor: null, hasMore: false },
+      });
+
+      const res = await app.inject({
+        method: 'GET',
+        url: '/api/v1/households/hh1/cabinet',
+        headers: authHeaders,
+      });
+
+      expect(res.statusCode).toBe(200);
+      const body = res.json();
+      expect(body.data[0].concentration).toBe(5.0);
+      expect(body.data[0].concentrationUnit).toBe('mg/mL');
+      expect(body.data[0].purchaseDate).toBe('2024-03-01T00:00:00.000Z');
+      expect(body.data[0].unitPrice).toBe(1.5);
+      expect(body.data[0].totalPrice).toBe(45.0);
+      expect(body.data[0].currency).toBe('USD');
+      expect(body.data[0].storeId).toBe('store-1');
+      expect(body.data[0].storeName).toBe('Pharmacy Plus');
+    });
   });
 
   describe('GET /api/v1/households/:householdId/cabinet/summary', () => {
@@ -379,4 +443,32 @@ describe('cabinet.routes', () => {
       expect(res.statusCode).toBe(204);
     });
   });
+
+  describe('POST /api/v1/households/:householdId/cabinet/:id/discard', () => {
+    it('discards a cabinet item', async () => {
+      mockFindById.mockResolvedValue(makeFakeCabinetItem({ quantity: 20 }));
+      mockDiscard.mockResolvedValue(makeFakeCabinetItem({ quantity: 0, isDeleted: true }));
+
+      const res = await app.inject({
+        method: 'POST',
+        url: '/api/v1/households/hh1/cabinet/ci-1/discard',
+        headers: authHeaders,
+        payload: { reason: 'expired' },
+      });
+
+      expect(res.statusCode).toBe(200);
+      expect(res.json().quantity).toBe(0);
+    });
+
+    it('returns 400 for missing reason', async () => {
+      const res = await app.inject({
+        method: 'POST',
+        url: '/api/v1/households/hh1/cabinet/ci-1/discard',
+        headers: authHeaders,
+        payload: {},
+      });
+
+      expect(res.statusCode).toBe(400);
+    });
+  });
 });
diff --git a/packages/api/src/modules/cabinet/cabinet.routes.ts b/packages/api/src/modules/cabinet/cabinet.routes.ts
index e1f03dd..8f4cbce 100644
--- a/packages/api/src/modules/cabinet/cabinet.routes.ts
+++ b/packages/api/src/modules/cabinet/cabinet.routes.ts
@@ -10,6 +10,7 @@ import {
   CabinetItemResponseSchema,
   CabinetItemListResponseSchema,
   CabinetSummaryResponseSchema,
+  DiscardCabinetItemSchema,
 } from '@meshitrack/shared';
 import { CabinetRepository } from './cabinet.repository.js';
 import { CabinetService } from './cabinet.service.js';
@@ -30,6 +31,12 @@ type AnyCabinetDoc = {
   unit: string;
   expirationDate?: Date | string | null;
   status: string;
+  purchaseDate?: Date | string | null;
+  unitPrice?: number | null;
+  totalPrice?: number | null;
+  currency?: string | null;
+  storeId?: string | null;
+  storeName?: string | null;
   notes?: string | null;
   createdBy: string;
   createdAt: string | { toISOString: () => string };
@@ -70,6 +77,12 @@ function toCabinetItemResponse(doc: AnyCabinetDoc): z.infer<typeof CabinetItemRe
     unit: doc.unit,
     ...(doc.expirationDate ? { expirationDate: toOptIso(doc.expirationDate) } : {}),
     status: doc.status,
+    ...(doc.purchaseDate ? { purchaseDate: toOptIso(doc.purchaseDate) } : {}),
+    ...(doc.unitPrice != null ? { unitPrice: doc.unitPrice } : {}),
+    ...(doc.totalPrice != null ? { totalPrice: doc.totalPrice } : {}),
+    ...(doc.currency ? { currency: doc.currency } : {}),
+    ...(doc.storeId ? { storeId: doc.storeId } : {}),
+    ...(doc.storeName ? { storeName: doc.storeName } : {}),
     ...(doc.notes ? { notes: doc.notes } : {}),
     createdBy: doc.createdBy,
     createdAt: toIso(doc.createdAt),
@@ -198,6 +211,7 @@ export default fp(
           request.params.id,
           request.params.householdId,
           request.body,
+          request.user.keycloakId,
         );
         return reply.send(toCabinetItemResponse(item));
       },
@@ -218,6 +232,8 @@ export default fp(
           request.params.id,
           request.params.householdId,
           request.body.delta,
+          request.user.keycloakId,
+          request.body.reason,
         );
         return reply.send(toCabinetItemResponse(item));
       },
@@ -233,10 +249,32 @@ export default fp(
       },
       handler: async (request, reply) => {
         const service = fastify.diContainer.resolve('cabinetService');
-        await service.delete(request.params.id, request.params.householdId);
+        await service.delete(request.params.id, request.params.householdId, request.user.keycloakId);
         return reply.status(204).send();
       },
     });
+
+    // POST /api/v1/households/:householdId/cabinet/:id/discard — discard item
+    app.route({
+      method: 'POST',
+      url: '/api/v1/households/:householdId/cabinet/:id/discard',
+      schema: {
+        params: householdParams.extend({ id: z.string() }),
+        body: DiscardCabinetItemSchema,
+        response: { 200: CabinetItemResponseSchema },
+      },
+      handler: async (request, reply) => {
+        const service = fastify.diContainer.resolve('cabinetService');
+        const item = await service.discard(
+          request.params.id,
+          request.params.householdId,
+          request.user.keycloakId,
+          request.body.reason,
+          request.body.notes,
+        );
+        return reply.send(toCabinetItemResponse(item));
+      },
+    });
   },
   {
     name: 'cabinet-routes',
diff --git a/packages/api/src/modules/cabinet/cabinet.service.test.ts b/packages/api/src/modules/cabinet/cabinet.service.test.ts
index 35aede6..56e3ced 100644
--- a/packages/api/src/modules/cabinet/cabinet.service.test.ts
+++ b/packages/api/src/modules/cabinet/cabinet.service.test.ts
@@ -1,5 +1,6 @@
 import { describe, it, expect, vi, beforeEach } from 'vitest';
 import { CabinetService } from './cabinet.service.js';
+import { CabinetEventType, CabinetEventSourceType } from '@meshitrack/shared';
 
 describe(CabinetService.name, () => {
   const mockCabinetRepo = {
@@ -12,6 +13,8 @@ describe(CabinetService.name, () => {
     findExpiringSoon: vi.fn(),
     softDelete: vi.fn(),
     countByMedicineId: vi.fn(),
+    discard: vi.fn(),
+    findActiveByMedicineForFEFO: vi.fn(),
   };
 
   const mockMedicinesRepo = {
@@ -32,6 +35,15 @@ describe(CabinetService.name, () => {
     countByMedicineId: vi.fn(),
   };
 
+  const mockCabinetEventsService = {
+    logEvent: vi.fn(),
+    logEvents: vi.fn(),
+    listEvents: vi.fn(),
+    getEventsByItem: vi.fn(),
+    getSpendingSummary: vi.fn(),
+    getAvgUnitPrices: vi.fn(),
+  };
+
   let service: CabinetService;
 
   beforeEach(() => {
@@ -40,6 +52,7 @@ describe(CabinetService.name, () => {
       cabinetRepository: mockCabinetRepo as never,
       medicinesRepository: mockMedicinesRepo as never,
       medicineProductsRepository: mockProductsRepo as never,
+      cabinetEventsService: mockCabinetEventsService as never,
     });
   });
 
@@ -150,6 +163,33 @@ describe(CabinetService.name, () => {
       );
     });
 
+    it('logs PURCHASED event after creation', async () => {
+      mockMedicinesRepo.findById.mockResolvedValue({
+        _id: 'med-1',
+        name: 'Metformin',
+        strength: 500,
+        strengthUnit: 'mg',
+        form: 'tablet',
+      });
+      mockCabinetRepo.create.mockResolvedValue({ _id: 'ci-1' });
+
+      await service.addItem(createInput, 'hh1', 'user-1');
+
+      expect(mockCabinetEventsService.logEvent).toHaveBeenCalledWith(
+        expect.objectContaining({
+          householdId: 'hh1',
+          userId: 'user-1',
+          cabinetItemId: 'ci-1',
+          medicineId: 'med-1',
+          eventType: CabinetEventType.PURCHASED,
+          quantity: 30,
+          quantityBefore: 0,
+          quantityAfter: 30,
+          sourceType: CabinetEventSourceType.MANUAL,
+        }),
+      );
+    });
+
     it('throws NotFoundError when medicine not found', async () => {
       mockMedicinesRepo.findById.mockResolvedValue(null);
 
@@ -199,28 +239,53 @@ describe(CabinetService.name, () => {
 
   describe('update', () => {
     it('updates and returns item', async () => {
-      mockCabinetRepo.findById.mockResolvedValue({ _id: 'ci-1' });
+      mockCabinetRepo.findById.mockResolvedValue({ _id: 'ci-1', quantity: 30, medicineId: 'med-1', medicineName: 'Test' });
       const updated = { _id: 'ci-1', quantity: 25 };
       mockCabinetRepo.update.mockResolvedValue(updated);
 
-      const result = await service.update('ci-1', 'hh1', { quantity: 25 });
+      const result = await service.update('ci-1', 'hh1', { quantity: 25 }, 'user-1');
 
       expect(result).toEqual(updated);
     });
 
+    it('logs ADJUSTED event when quantity changes', async () => {
+      mockCabinetRepo.findById.mockResolvedValue({ _id: 'ci-1', quantity: 30, medicineId: 'med-1', medicineName: 'Test' });
+      mockCabinetRepo.update.mockResolvedValue({ _id: 'ci-1', quantity: 25 });
+
+      await service.update('ci-1', 'hh1', { quantity: 25 }, 'user-1');
+
+      expect(mockCabinetEventsService.logEvent).toHaveBeenCalledWith(
+        expect.objectContaining({
+          eventType: CabinetEventType.ADJUSTED,
+          quantity: -5,
+          quantityBefore: 30,
+          quantityAfter: 25,
+        }),
+      );
+    });
+
+    it('does not log event when quantity unchanged', async () => {
+      mockCabinetRepo.findById.mockResolvedValue({ _id: 'ci-1', quantity: 30, medicineId: 'med-1', medicineName: 'Test' });
+      mockCabinetRepo.update.mockResolvedValue({ _id: 'ci-1', quantity: 30 });
+
+      await service.update('ci-1', 'hh1', { notes: 'updated' }, 'user-1');
+
+      expect(mockCabinetEventsService.logEvent).not.toHaveBeenCalled();
+    });
+
     it('throws NotFoundError when item does not exist', async () => {
       mockCabinetRepo.findById.mockResolvedValue(null);
 
-      await expect(service.update('ci-missing', 'hh1', { quantity: 25 })).rejects.toThrow(
+      await expect(service.update('ci-missing', 'hh1', { quantity: 25 }, 'user-1')).rejects.toThrow(
         'Cabinet item not found',
       );
     });
 
     it('throws NotFoundError when update returns null', async () => {
-      mockCabinetRepo.findById.mockResolvedValue({ _id: 'ci-1' });
+      mockCabinetRepo.findById.mockResolvedValue({ _id: 'ci-1', quantity: 30, medicineId: 'med-1', medicineName: 'Test' });
       mockCabinetRepo.update.mockResolvedValue(null);
 
-      await expect(service.update('ci-1', 'hh1', { quantity: 25 })).rejects.toThrow(
+      await expect(service.update('ci-1', 'hh1', { quantity: 25 }, 'user-1')).rejects.toThrow(
         'Cabinet item not found',
       );
     });
@@ -228,17 +293,34 @@ describe(CabinetService.name, () => {
 
   describe('adjustQuantity', () => {
     it('adjusts quantity and returns item', async () => {
-      mockCabinetRepo.findById.mockResolvedValue({ _id: 'ci-1', quantity: 30 });
+      mockCabinetRepo.findById.mockResolvedValue({ _id: 'ci-1', quantity: 30, medicineId: 'med-1', medicineName: 'Test' });
       const updated = { _id: 'ci-1', quantity: 27 };
       mockCabinetRepo.adjustQuantity.mockResolvedValue(updated);
 
-      const result = await service.adjustQuantity('ci-1', 'hh1', -3);
+      const result = await service.adjustQuantity('ci-1', 'hh1', -3, 'user-1');
 
       expect(result).toEqual(updated);
     });
 
+    it('logs ADJUSTED event', async () => {
+      mockCabinetRepo.findById.mockResolvedValue({ _id: 'ci-1', quantity: 30, medicineId: 'med-1', medicineName: 'Test' });
+      mockCabinetRepo.adjustQuantity.mockResolvedValue({ _id: 'ci-1', quantity: 27 });
+
+      await service.adjustQuantity('ci-1', 'hh1', -3, 'user-1', 'took some');
+
+      expect(mockCabinetEventsService.logEvent).toHaveBeenCalledWith(
+        expect.objectContaining({
+          eventType: CabinetEventType.ADJUSTED,
+          quantity: -3,
+          quantityBefore: 30,
+          quantityAfter: 27,
+          reason: 'took some',
+        }),
+      );
+    });
+
     it('throws BadRequestError when delta is 0', async () => {
-      await expect(service.adjustQuantity('ci-1', 'hh1', 0)).rejects.toThrow(
+      await expect(service.adjustQuantity('ci-1', 'hh1', 0, 'user-1')).rejects.toThrow(
         'Delta must be non-zero',
       );
     });
@@ -246,16 +328,16 @@ describe(CabinetService.name, () => {
     it('throws NotFoundError when item does not exist', async () => {
       mockCabinetRepo.findById.mockResolvedValue(null);
 
-      await expect(service.adjustQuantity('ci-missing', 'hh1', 5)).rejects.toThrow(
+      await expect(service.adjustQuantity('ci-missing', 'hh1', 5, 'user-1')).rejects.toThrow(
         'Cabinet item not found',
       );
     });
 
     it('throws NotFoundError when adjust returns null', async () => {
-      mockCabinetRepo.findById.mockResolvedValue({ _id: 'ci-1' });
+      mockCabinetRepo.findById.mockResolvedValue({ _id: 'ci-1', quantity: 30, medicineId: 'med-1', medicineName: 'Test' });
       mockCabinetRepo.adjustQuantity.mockResolvedValue(null);
 
-      await expect(service.adjustQuantity('ci-1', 'hh1', 5)).rejects.toThrow(
+      await expect(service.adjustQuantity('ci-1', 'hh1', 5, 'user-1')).rejects.toThrow(
         'Cabinet item not found',
       );
     });
@@ -274,26 +356,81 @@ describe(CabinetService.name, () => {
   });
 
   describe('delete', () => {
-    it('soft deletes item', async () => {
-      mockCabinetRepo.findById.mockResolvedValue({ _id: 'ci-1' });
+    it('soft deletes item and logs DELETED event', async () => {
+      mockCabinetRepo.findById.mockResolvedValue({ _id: 'ci-1', quantity: 10, medicineId: 'med-1', medicineName: 'Test' });
       mockCabinetRepo.softDelete.mockResolvedValue({ _id: 'ci-1', isDeleted: true });
 
-      const result = await service.delete('ci-1', 'hh1');
+      const result = await service.delete('ci-1', 'hh1', 'user-1');
 
       expect(result.isDeleted).toBe(true);
+      expect(mockCabinetEventsService.logEvent).toHaveBeenCalledWith(
+        expect.objectContaining({
+          eventType: CabinetEventType.DELETED,
+          quantity: -10,
+          quantityBefore: 10,
+          quantityAfter: 0,
+        }),
+      );
     });
 
     it('throws NotFoundError when item does not exist', async () => {
       mockCabinetRepo.findById.mockResolvedValue(null);
 
-      await expect(service.delete('ci-missing', 'hh1')).rejects.toThrow('Cabinet item not found');
+      await expect(service.delete('ci-missing', 'hh1', 'user-1')).rejects.toThrow('Cabinet item not found');
     });
 
     it('throws NotFoundError when softDelete returns null', async () => {
-      mockCabinetRepo.findById.mockResolvedValue({ _id: 'ci-1' });
+      mockCabinetRepo.findById.mockResolvedValue({ _id: 'ci-1', quantity: 5, medicineId: 'med-1', medicineName: 'Test' });
       mockCabinetRepo.softDelete.mockResolvedValue(null);
 
-      await expect(service.delete('ci-1', 'hh1')).rejects.toThrow('Cabinet item not found');
+      await expect(service.delete('ci-1', 'hh1', 'user-1')).rejects.toThrow('Cabinet item not found');
+    });
+  });
+
+  describe('discard', () => {
+    it('discards item and logs DISCARDED event', async () => {
+      mockCabinetRepo.findById.mockResolvedValue({ _id: 'ci-1', quantity: 20, medicineId: 'med-1', medicineName: 'Test' });
+      mockCabinetRepo.discard.mockResolvedValue({ _id: 'ci-1', quantity: 0, isDeleted: true });
+
+      const result = await service.discard('ci-1', 'hh1', 'user-1', 'expired', 'smelled off');
+
+      expect(result.quantity).toBe(0);
+      expect(result.isDeleted).toBe(true);
+      expect(mockCabinetEventsService.logEvent).toHaveBeenCalledWith(
+        expect.objectContaining({
+          eventType: CabinetEventType.DISCARDED,
+          quantity: -20,
+          quantityBefore: 20,
+          quantityAfter: 0,
+          reason: 'expired',
+          notes: 'smelled off',
+        }),
+      );
+    });
+
+    it('throws BadRequestError when quantity is zero', async () => {
+      mockCabinetRepo.findById.mockResolvedValue({ _id: 'ci-1', quantity: 0, medicineId: 'med-1', medicineName: 'Test' });
+
+      await expect(service.discard('ci-1', 'hh1', 'user-1', 'expired')).rejects.toThrow(
+        'Cannot discard an item with zero quantity',
+      );
+    });
+
+    it('throws NotFoundError when item does not exist', async () => {
+      mockCabinetRepo.findById.mockResolvedValue(null);
+
+      await expect(service.discard('ci-missing', 'hh1', 'user-1', 'expired')).rejects.toThrow(
+        'Cabinet item not found',
+      );
+    });
+
+    it('throws NotFoundError when discard returns null', async () => {
+      mockCabinetRepo.findById.mockResolvedValue({ _id: 'ci-1', quantity: 10, medicineId: 'med-1', medicineName: 'Test' });
+      mockCabinetRepo.discard.mockResolvedValue(null);
+
+      await expect(service.discard('ci-1', 'hh1', 'user-1', 'expired')).rejects.toThrow(
+        'Cabinet item not found',
+      );
     });
   });
 });
diff --git a/packages/api/src/modules/cabinet/cabinet.service.ts b/packages/api/src/modules/cabinet/cabinet.service.ts
index 55d443c..c043ff4 100644
--- a/packages/api/src/modules/cabinet/cabinet.service.ts
+++ b/packages/api/src/modules/cabinet/cabinet.service.ts
@@ -1,6 +1,11 @@
 import type { CabinetRepository } from './cabinet.repository.js';
 import type { MedicinesRepository } from '../medicines/medicines.repository.js';
 import type { MedicineProductsRepository } from '../medicine-products/medicine-products.repository.js';
+import type { CabinetEventsService } from '../cabinet-events/cabinet-events.service.js';
+import {
+  CabinetEventType,
+  CabinetEventSourceType,
+} from '@meshitrack/shared';
 import type {
   CreateCabinetItemInput,
   UpdateCabinetItemInput,
@@ -12,17 +17,25 @@ interface Deps {
   cabinetRepository: CabinetRepository;
   medicinesRepository: MedicinesRepository;
   medicineProductsRepository: MedicineProductsRepository;
+  cabinetEventsService: CabinetEventsService;
 }
 
 export class CabinetService {
   private readonly cabinetRepository: CabinetRepository;
   private readonly medicinesRepository: MedicinesRepository;
   private readonly medicineProductsRepository: MedicineProductsRepository;
+  private readonly cabinetEventsService: CabinetEventsService;
 
-  public constructor({ cabinetRepository, medicinesRepository, medicineProductsRepository }: Deps) {
+  public constructor({
+    cabinetRepository,
+    medicinesRepository,
+    medicineProductsRepository,
+    cabinetEventsService,
+  }: Deps) {
     this.cabinetRepository = cabinetRepository;
     this.medicinesRepository = medicinesRepository;
     this.medicineProductsRepository = medicineProductsRepository;
+    this.cabinetEventsService = cabinetEventsService;
   }
 
   public async list(householdId: string, query: CabinetQueryInput) {
@@ -74,7 +87,7 @@ export class CabinetService {
       concentrationUnit = product.concentrationUnit ?? undefined;
     }
 
-    return this.cabinetRepository.create(
+    const item = await this.cabinetRepository.create(
       {
         ...data,
         medicineName: medicine.name,
@@ -88,23 +101,80 @@ export class CabinetService {
       householdId,
       createdBy,
     );
+
+    await this.cabinetEventsService.logEvent({
+      householdId,
+      userId: createdBy,
+      cabinetItemId: item._id.toString(),
+      medicineId: data.medicineId,
+      medicineName: medicine.name,
+      eventType: CabinetEventType.PURCHASED,
+      quantity: data.quantity,
+      quantityBefore: 0,
+      quantityAfter: data.quantity,
+      unitPrice: data.unitPrice,
+      totalPrice: data.totalPrice,
+      currency: data.currency,
+      storeId: data.storeId,
+      storeName: data.storeName,
+      sourceType: CabinetEventSourceType.MANUAL,
+    });
+
+    return item;
   }
 
-  public async update(id: string, householdId: string, data: UpdateCabinetItemInput) {
-    await this.getById(id, householdId);
+  public async update(id: string, householdId: string, data: UpdateCabinetItemInput, userId: string) {
+    const existing = await this.getById(id, householdId);
     const updated = await this.cabinetRepository.update(id, householdId, data);
     if (!updated) throw new NotFoundError('Cabinet item not found');
+
+    if (data.quantity !== undefined && data.quantity !== existing.quantity) {
+      await this.cabinetEventsService.logEvent({
+        householdId,
+        userId,
+        cabinetItemId: id,
+        medicineId: existing.medicineId,
+        medicineName: existing.medicineName,
+        eventType: CabinetEventType.ADJUSTED,
+        quantity: data.quantity - existing.quantity,
+        quantityBefore: existing.quantity,
+        quantityAfter: data.quantity,
+        sourceType: CabinetEventSourceType.MANUAL,
+      });
+    }
+
     return updated;
   }
 
-  public async adjustQuantity(id: string, householdId: string, delta: number) {
+  public async adjustQuantity(
+    id: string,
+    householdId: string,
+    delta: number,
+    userId: string,
+    reason?: string,
+  ) {
     if (delta === 0) {
       throw new BadRequestError('Delta must be non-zero');
     }
 
-    await this.getById(id, householdId);
+    const existing = await this.getById(id, householdId);
     const updated = await this.cabinetRepository.adjustQuantity(id, householdId, delta);
     if (!updated) throw new NotFoundError('Cabinet item not found');
+
+    await this.cabinetEventsService.logEvent({
+      householdId,
+      userId,
+      cabinetItemId: id,
+      medicineId: existing.medicineId,
+      medicineName: existing.medicineName,
+      eventType: CabinetEventType.ADJUSTED,
+      quantity: delta,
+      quantityBefore: existing.quantity,
+      quantityAfter: updated.quantity,
+      reason,
+      sourceType: CabinetEventSourceType.MANUAL,
+    });
+
     return updated;
   }
 
@@ -112,10 +182,51 @@ export class CabinetService {
     return this.cabinetRepository.findExpiringSoon(householdId, withinDays);
   }
 
-  public async delete(id: string, householdId: string) {
-    await this.getById(id, householdId);
+  public async delete(id: string, householdId: string, userId: string) {
+    const existing = await this.getById(id, householdId);
     const deleted = await this.cabinetRepository.softDelete(id, householdId);
     if (!deleted) throw new NotFoundError('Cabinet item not found');
+
+    await this.cabinetEventsService.logEvent({
+      householdId,
+      userId,
+      cabinetItemId: id,
+      medicineId: existing.medicineId,
+      medicineName: existing.medicineName,
+      eventType: CabinetEventType.DELETED,
+      quantity: -existing.quantity,
+      quantityBefore: existing.quantity,
+      quantityAfter: 0,
+      sourceType: CabinetEventSourceType.MANUAL,
+    });
+
     return deleted;
   }
+
+  public async discard(id: string, householdId: string, userId: string, reason: string, notes?: string) {
+    const existing = await this.getById(id, householdId);
+    if (existing.quantity === 0) {
+      throw new BadRequestError('Cannot discard an item with zero quantity');
+    }
+
+    const discarded = await this.cabinetRepository.discard(id, householdId);
+    if (!discarded) throw new NotFoundError('Cabinet item not found');
+
+    await this.cabinetEventsService.logEvent({
+      householdId,
+      userId,
+      cabinetItemId: id,
+      medicineId: existing.medicineId,
+      medicineName: existing.medicineName,
+      eventType: CabinetEventType.DISCARDED,
+      quantity: -existing.quantity,
+      quantityBefore: existing.quantity,
+      quantityAfter: 0,
+      reason,
+      notes,
+      sourceType: CabinetEventSourceType.MANUAL,
+    });
+
+    return discarded;
+  }
 }
diff --git a/packages/api/src/modules/organizer/organizer.repository.test.ts b/packages/api/src/modules/organizer/organizer.repository.test.ts
new file mode 100644
index 0000000..ab51f95
--- /dev/null
+++ b/packages/api/src/modules/organizer/organizer.repository.test.ts
@@ -0,0 +1,183 @@
+import { describe, it, expect, vi, beforeEach } from 'vitest';
+
+const { mockFind, mockFindOne, mockFindOneAndUpdate, mockSave } = vi.hoisted(() => ({
+  mockFind: vi.fn(),
+  mockFindOne: vi.fn(),
+  mockFindOneAndUpdate: vi.fn(),
+  mockSave: vi.fn(),
+}));
+
+vi.mock('../../schemas/organizer-fill.schema.js', () => {
+  const chain = () => ({
+    sort: vi.fn().mockReturnThis(),
+    limit: vi.fn().mockReturnThis(),
+    lean: vi.fn().mockReturnThis(),
+    exec: mockFind,
+  });
+
+  const findOneChain = () => ({
+    lean: vi.fn().mockReturnThis(),
+    exec: mockFindOne,
+  });
+
+  const updateChain = () => ({
+    exec: mockFindOneAndUpdate,
+  });
+
+  class FakeModel {
+    data: unknown;
+    constructor(data: unknown) {
+      this.data = data;
+    }
+    save = mockSave;
+    toObject() {
+      return this.data;
+    }
+    static find = vi.fn(() => chain());
+    static findOne = vi.fn(() => findOneChain());
+    static findOneAndUpdate = vi.fn(() => updateChain());
+  }
+
+  return { OrganizerFillModel: FakeModel };
+});
+
+import { OrganizerRepository } from './organizer.repository.js';
+
+describe(OrganizerRepository.name, () => {
+  let repo: OrganizerRepository;
+
+  beforeEach(() => {
+    vi.clearAllMocks();
+    repo = new OrganizerRepository();
+  });
+
+  describe('findByHousehold', () => {
+    it('returns paginated items', async () => {
+      const items = [{ _id: 'fill-1', regimenName: 'Morning' }];
+      mockFind.mockResolvedValue(items);
+
+      const result = await repo.findByHousehold('hh1', 'user-1', { limit: 20 });
+
+      expect(result.data).toEqual(items);
+      expect(result.pagination.hasMore).toBe(false);
+    });
+
+    it('handles cursor-based pagination', async () => {
+      const items = [{ _id: 'fill-2', regimenName: 'Evening' }];
+      mockFind.mockResolvedValue(items);
+
+      const cursor = Buffer.from('fill-1').toString('base64');
+      const result = await repo.findByHousehold('hh1', 'user-1', { cursor, limit: 20 });
+
+      expect(result.data).toEqual(items);
+      expect(result.pagination.hasMore).toBe(false);
+    });
+
+    it('sets hasMore when more items exist', async () => {
+      const items = Array.from({ length: 3 }, (_, i) => ({ _id: `fill-${i}`, regimenName: `R${i}` }));
+      mockFind.mockResolvedValue(items);
+
+      const result = await repo.findByHousehold('hh1', 'user-1', { limit: 2 });
+
+      expect(result.data).toHaveLength(2);
+      expect(result.pagination.hasMore).toBe(true);
+      expect(result.pagination.cursor).toBeTruthy();
+    });
+
+    it('returns null cursor when no data', async () => {
+      mockFind.mockResolvedValue([]);
+
+      const result = await repo.findByHousehold('hh1', 'user-1', { limit: 20 });
+
+      expect(result.pagination.cursor).toBeNull();
+      expect(result.pagination.hasMore).toBe(false);
+    });
+
+    it('filters by regimenId', async () => {
+      mockFind.mockResolvedValue([]);
+
+      await repo.findByHousehold('hh1', 'user-1', { regimenId: 'reg-1', limit: 20 });
+
+      expect(mockFind).toHaveBeenCalled();
+    });
+
+    it('filters by status', async () => {
+      mockFind.mockResolvedValue([]);
+
+      await repo.findByHousehold('hh1', 'user-1', { status: 'completed' as never, limit: 20 });
+
+      expect(mockFind).toHaveBeenCalled();
+    });
+
+    it('returns cursor as null when hasMore is false even with data', async () => {
+      const items = [{ _id: 'fill-1', regimenName: 'Morning' }];
+      mockFind.mockResolvedValue(items);
+
+      const result = await repo.findByHousehold('hh1', 'user-1', { limit: 20 });
+
+      expect(result.pagination.cursor).toBeNull();
+      expect(result.pagination.hasMore).toBe(false);
+    });
+  });
+
+  describe('findById', () => {
+    it('returns fill by id and householdId', async () => {
+      const fill = { _id: 'fill-1', householdId: 'hh1', regimenName: 'Morning' };
+      mockFindOne.mockResolvedValue(fill);
+
+      const result = await repo.findById('fill-1', 'hh1');
+
+      expect(result).toEqual(fill);
+    });
+
+    it('returns null when not found', async () => {
+      mockFindOne.mockResolvedValue(null);
+
+      const result = await repo.findById('fill-missing', 'hh1');
+
+      expect(result).toBeNull();
+    });
+  });
+
+  describe('create', () => {
+    it('creates and returns organizer fill', async () => {
+      const data = {
+        householdId: 'hh1',
+        userId: 'user-1',
+        regimenId: 'reg-1',
+        regimenName: 'Morning',
+        numberOfDays: 7,
+        fillDate: new Date(),
+        items: [],
+        status: 'completed' as const,
+      };
+      mockSave.mockImplementation(function (this: { toObject: () => unknown }) {
+        return Promise.resolve(this);
+      });
+
+      const result = await repo.create(data as never);
+
+      expect(result).toBeTruthy();
+      expect(mockSave).toHaveBeenCalled();
+    });
+  });
+
+  describe('updateStatus', () => {
+    it('updates and returns fill with new status', async () => {
+      const updated = { _id: 'fill-1', status: 'reversed' };
+      mockFindOneAndUpdate.mockResolvedValue(updated);
+
+      const result = await repo.updateStatus('fill-1', 'hh1', 'reversed' as never);
+
+      expect(result).toEqual(updated);
+    });
+
+    it('returns null when fill not found', async () => {
+      mockFindOneAndUpdate.mockResolvedValue(null);
+
+      const result = await repo.updateStatus('fill-missing', 'hh1', 'reversed' as never);
+
+      expect(result).toBeNull();
+    });
+  });
+});
diff --git a/packages/api/src/modules/organizer/organizer.repository.ts b/packages/api/src/modules/organizer/organizer.repository.ts
new file mode 100644
index 0000000..299769c
--- /dev/null
+++ b/packages/api/src/modules/organizer/organizer.repository.ts
@@ -0,0 +1,77 @@
+import { OrganizerFillModel } from '../../schemas/organizer-fill.schema.js';
+import type { OrganizerFillStatus } from '@meshitrack/shared';
+
+interface OrganizerFillItemData {
+  medicineId: string;
+  medicineName: string;
+  quantityNeeded: number;
+  quantityTaken: number;
+  wasShort: boolean;
+  shortage: number;
+  deductions: { cabinetItemId: string; quantityTaken: number }[];
+}
+
+interface CreateOrganizerFillData {
+  householdId: string;
+  userId: string;
+  regimenId: string;
+  regimenName: string;
+  numberOfDays: number;
+  fillDate: Date;
+  items: OrganizerFillItemData[];
+  status: OrganizerFillStatus;
+  notes?: string;
+}
+
+interface FindByHouseholdQuery {
+  regimenId?: string;
+  status?: OrganizerFillStatus;
+  cursor?: string;
+  limit: number;
+}
+
+export class OrganizerRepository {
+  public async findByHousehold(householdId: string, userId: string, query: FindByHouseholdQuery) {
+    const filter: Record<string, unknown> = { householdId, userId };
+
+    if (query.regimenId) filter['regimenId'] = query.regimenId;
+    if (query.status) filter['status'] = query.status;
+
+    if (query.cursor) {
+      const id = Buffer.from(query.cursor, 'base64').toString();
+      filter['_id'] = { $lt: id };
+    }
+
+    const limit = query.limit;
+    const items = await OrganizerFillModel.find(filter)
+      .sort({ _id: -1 })
+      .limit(limit + 1)
+      .lean()
+      .exec();
+
+    const hasMore = items.length > limit;
+    const data = hasMore ? items.slice(0, limit) : items;
+    const cursor =
+      data.length > 0 ? Buffer.from(data[data.length - 1]._id.toString()).toString('base64') : null;
+
+    return { data, pagination: { cursor: hasMore ? cursor : null, hasMore } };
+  }
+
+  public async findById(id: string, householdId: string) {
+    return OrganizerFillModel.findOne({ _id: id, householdId }).lean().exec();
+  }
+
+  public async create(data: CreateOrganizerFillData) {
+    const fill = new OrganizerFillModel(data);
+    const saved = await fill.save();
+    return saved.toObject();
+  }
+
+  public async updateStatus(id: string, householdId: string, status: OrganizerFillStatus) {
+    return OrganizerFillModel.findOneAndUpdate(
+      { _id: id, householdId },
+      { $set: { status } },
+      { new: true, lean: true },
+    ).exec();
+  }
+}
diff --git a/packages/api/src/modules/organizer/organizer.routes.test.ts b/packages/api/src/modules/organizer/organizer.routes.test.ts
new file mode 100644
index 0000000..d74133a
--- /dev/null
+++ b/packages/api/src/modules/organizer/organizer.routes.test.ts
@@ -0,0 +1,478 @@
+import { describe, it, expect, vi, beforeEach, afterEach } from 'vitest';
+import Fastify from 'fastify';
+import { fastifyAwilixPlugin } from '@fastify/awilix';
+import { serializerCompiler, validatorCompiler } from 'fastify-type-provider-zod';
+import { OrganizerFillStatus } from '@meshitrack/shared';
+
+vi.mock('jose', () => ({
+  createRemoteJWKSet: vi.fn(() => 'mock-jwks'),
+  jwtVerify: vi.fn().mockResolvedValue({
+    payload: {
+      sub: 'kc-1',
+      email: 'test@example.com',
+      preferred_username: 'testuser',
+      realm_access: { roles: ['member'] },
+      householdIds: ['hh1'],
+    },
+    protectedHeader: { alg: 'RS256' },
+    key: {},
+  }),
+}));
+
+const { mockListFills, mockGetFillById, mockPreview, mockFill, mockUndoFill } = vi.hoisted(() => ({
+  mockListFills: vi.fn(),
+  mockGetFillById: vi.fn(),
+  mockPreview: vi.fn(),
+  mockFill: vi.fn(),
+  mockUndoFill: vi.fn(),
+}));
+
+vi.mock('./organizer.repository.js', () => ({
+  OrganizerRepository: class {
+    create = vi.fn();
+    update = vi.fn();
+    findById = vi.fn();
+    findByHousehold = vi.fn();
+    updateStatus = vi.fn();
+  },
+}));
+
+vi.mock('./organizer.service.js', () => ({
+  OrganizerService: class {
+    listFills = mockListFills;
+    getFillById = mockGetFillById;
+    preview = mockPreview;
+    fill = mockFill;
+    undoFill = mockUndoFill;
+  },
+}));
+
+vi.mock('../users/users.repository.js', () => ({
+  UsersRepository: class {
+    findByKeycloakId = vi.fn().mockResolvedValue({ householdIds: ['hh1'] });
+    upsertFromToken = vi.fn().mockResolvedValue({ householdIds: ['hh1'] });
+  },
+}));
+
+import authPlugin from '../../plugins/auth.plugin.js';
+import householdPlugin from '../../plugins/household.plugin.js';
+import usersRoutes from '../users/users.routes.js';
+import organizerRoutes from './organizer.routes.js';
+
+function makeFakeFill(overrides = {}) {
+  return {
+    _id: 'fill-1',
+    householdId: 'hh1',
+    userId: 'kc-1',
+    regimenId: 'reg-1',
+    regimenName: 'Daily Medications',
+    numberOfDays: 7,
+    fillDate: '2024-06-01T00:00:00.000Z',
+    items: [
+      {
+        medicineId: 'med-1',
+        medicineName: 'Metformin',
+        quantityNeeded: 7,
+        quantityTaken: 7,
+        wasShort: false,
+        shortage: 0,
+        deductions: [
+          { cabinetItemId: 'ci-1', quantityTaken: 7 },
+        ],
+      },
+    ],
+    status: OrganizerFillStatus.COMPLETED,
+    notes: null,
+    createdAt: '2024-06-01T00:00:00.000Z',
+    updatedAt: '2024-06-01T00:00:00.000Z',
+    ...overrides,
+  };
+}
+
+function makeFakePreview(overrides = {}) {
+  return {
+    regimenName: 'Daily Medications',
+    numberOfDays: 7,
+    items: [
+      {
+        medicineId: 'med-1',
+        medicineName: 'Metformin',
+        quantityNeeded: 7,
+        quantityAvailable: 30,
+        isShort: false,
+        shortage: 0,
+        cabinetBreakdown: [
+          {
+            cabinetItemId: 'ci-1',
+            expirationDate: '2025-12-31T00:00:00.000Z',
+            quantityToTake: 7,
+          },
+        ],
+      },
+    ],
+    canFillCompletely: true,
+    hasShortages: false,
+    ...overrides,
+  };
+}
+
+describe('organizer.routes', () => {
+  let app: Awaited<ReturnType<typeof buildTestApp>>;
+
+  async function buildTestApp() {
+    const instance = Fastify({ logger: false });
+    instance.setValidatorCompiler(validatorCompiler);
+    instance.setSerializerCompiler(serializerCompiler);
+    await instance.register(fastifyAwilixPlugin, {
+      disposeOnClose: true,
+      disposeOnResponse: true,
+      strictBooleanEnforced: true,
+    });
+    await instance.register(authPlugin);
+    await instance.register(householdPlugin);
+    await instance.register(usersRoutes);
+    await instance.register(organizerRoutes);
+    await instance.ready();
+    return instance;
+  }
+
+  const authHeaders = { authorization: 'Bearer valid-token' };
+
+  beforeEach(async () => {
+    vi.clearAllMocks();
+    app = await buildTestApp();
+  });
+
+  afterEach(async () => {
+    if (app) await app.close();
+  });
+
+  describe('GET /api/v1/households/:householdId/organizer/fills', () => {
+    it('returns paginated fill list', async () => {
+      const fill = makeFakeFill();
+      mockListFills.mockResolvedValue({
+        data: [fill],
+        pagination: { cursor: null, hasMore: false },
+      });
+
+      const res = await app.inject({
+        method: 'GET',
+        url: '/api/v1/households/hh1/organizer/fills',
+        headers: authHeaders,
+      });
+
+      expect(res.statusCode).toBe(200);
+      const body = res.json();
+      expect(body.data).toHaveLength(1);
+      expect(body.data[0].regimenName).toBe('Daily Medications');
+      expect(body.data[0].status).toBe(OrganizerFillStatus.COMPLETED);
+      expect(body.pagination.hasMore).toBe(false);
+    });
+
+    it('passes query parameters to service', async () => {
+      mockListFills.mockResolvedValue({
+        data: [],
+        pagination: { cursor: null, hasMore: false },
+      });
+
+      const res = await app.inject({
+        method: 'GET',
+        url: '/api/v1/households/hh1/organizer/fills?regimenId=reg-1&status=completed&limit=10',
+        headers: authHeaders,
+      });
+
+      expect(res.statusCode).toBe(200);
+      expect(mockListFills).toHaveBeenCalledWith('hh1', 'kc-1', expect.objectContaining({
+        regimenId: 'reg-1',
+        status: OrganizerFillStatus.COMPLETED,
+        limit: 10,
+      }));
+    });
+
+    it('handles ObjectId and Date serialization in fill response', async () => {
+      const fill = makeFakeFill({
+        _id: { toString: () => 'fill-obj' },
+        fillDate: new Date('2024-06-01T00:00:00.000Z'),
+        createdAt: { toISOString: () => '2024-06-01T00:00:00.000Z' },
+        updatedAt: new Date('2024-06-02T00:00:00.000Z'),
+      });
+      mockListFills.mockResolvedValue({
+        data: [fill],
+        pagination: { cursor: null, hasMore: false },
+      });
+
+      const res = await app.inject({
+        method: 'GET',
+        url: '/api/v1/households/hh1/organizer/fills',
+        headers: authHeaders,
+      });
+
+      expect(res.statusCode).toBe(200);
+      const body = res.json();
+      expect(body.data[0]._id).toBe('fill-obj');
+      expect(body.data[0].fillDate).toBe('2024-06-01T00:00:00.000Z');
+      expect(body.data[0].createdAt).toBe('2024-06-01T00:00:00.000Z');
+      expect(body.data[0].updatedAt).toBe('2024-06-02T00:00:00.000Z');
+    });
+
+    it('omits notes from response when null', async () => {
+      const fill = makeFakeFill({ notes: null });
+      mockListFills.mockResolvedValue({
+        data: [fill],
+        pagination: { cursor: null, hasMore: false },
+      });
+
+      const res = await app.inject({
+        method: 'GET',
+        url: '/api/v1/households/hh1/organizer/fills',
+        headers: authHeaders,
+      });
+
+      expect(res.statusCode).toBe(200);
+      const body = res.json();
+      expect(body.data[0].notes).toBeUndefined();
+    });
+
+    it('includes notes in response when present', async () => {
+      const fill = makeFakeFill({ notes: 'Refilled before holiday' });
+      mockListFills.mockResolvedValue({
+        data: [fill],
+        pagination: { cursor: null, hasMore: false },
+      });
+
+      const res = await app.inject({
+        method: 'GET',
+        url: '/api/v1/households/hh1/organizer/fills',
+        headers: authHeaders,
+      });
+
+      expect(res.statusCode).toBe(200);
+      const body = res.json();
+      expect(body.data[0].notes).toBe('Refilled before holiday');
+    });
+  });
+
+  describe('GET /api/v1/households/:householdId/organizer/fills/:id', () => {
+    it('returns single fill by id', async () => {
+      const fill = makeFakeFill();
+      mockGetFillById.mockResolvedValue(fill);
+
+      const res = await app.inject({
+        method: 'GET',
+        url: '/api/v1/households/hh1/organizer/fills/fill-1',
+        headers: authHeaders,
+      });
+
+      expect(res.statusCode).toBe(200);
+      const body = res.json();
+      expect(body._id).toBe('fill-1');
+      expect(body.regimenId).toBe('reg-1');
+      expect(body.items).toHaveLength(1);
+      expect(body.items[0].deductions).toHaveLength(1);
+      expect(body.items[0].deductions[0].cabinetItemId).toBe('ci-1');
+    });
+
+    it('passes id and householdId to service correctly', async () => {
+      const fill = makeFakeFill();
+      mockGetFillById.mockResolvedValue(fill);
+
+      const res = await app.inject({
+        method: 'GET',
+        url: '/api/v1/households/hh1/organizer/fills/fill-42',
+        headers: authHeaders,
+      });
+
+      expect(res.statusCode).toBe(200);
+      expect(mockGetFillById).toHaveBeenCalledWith('fill-42', 'hh1');
+    });
+  });
+
+  describe('POST /api/v1/households/:householdId/organizer/preview', () => {
+    it('returns preview result with items and shortage info', async () => {
+      const preview = makeFakePreview();
+      mockPreview.mockResolvedValue(preview);
+
+      const res = await app.inject({
+        method: 'POST',
+        url: '/api/v1/households/hh1/organizer/preview',
+        headers: { ...authHeaders, 'content-type': 'application/json' },
+        payload: { regimenId: 'reg-1', numberOfDays: 7 },
+      });
+
+      expect(res.statusCode).toBe(200);
+      const body = res.json();
+      expect(body.regimenName).toBe('Daily Medications');
+      expect(body.canFillCompletely).toBe(true);
+      expect(body.hasShortages).toBe(false);
+      expect(body.items).toHaveLength(1);
+      expect(body.items[0].medicineName).toBe('Metformin');
+      expect(body.items[0].cabinetBreakdown).toHaveLength(1);
+    });
+
+    it('passes regimenId and numberOfDays to service', async () => {
+      const preview = makeFakePreview();
+      mockPreview.mockResolvedValue(preview);
+
+      const res = await app.inject({
+        method: 'POST',
+        url: '/api/v1/households/hh1/organizer/preview',
+        headers: { ...authHeaders, 'content-type': 'application/json' },
+        payload: { regimenId: 'reg-99', numberOfDays: 14 },
+      });
+
+      expect(res.statusCode).toBe(200);
+      expect(mockPreview).toHaveBeenCalledWith('hh1', 'kc-1', 'reg-99', 14);
+    });
+
+    it('returns preview with hasShortages=true and isShort items', async () => {
+      const preview = makeFakePreview({
+        canFillCompletely: false,
+        hasShortages: true,
+        items: [
+          {
+            medicineId: 'med-1',
+            medicineName: 'Metformin',
+            quantityNeeded: 14,
+            quantityAvailable: 5,
+            isShort: true,
+            shortage: 9,
+            cabinetBreakdown: [
+              {
+                cabinetItemId: 'ci-1',
+                expirationDate: '2025-12-31T00:00:00.000Z',
+                quantityToTake: 5,
+              },
+            ],
+          },
+        ],
+      });
+      mockPreview.mockResolvedValue(preview);
+
+      const res = await app.inject({
+        method: 'POST',
+        url: '/api/v1/households/hh1/organizer/preview',
+        headers: { ...authHeaders, 'content-type': 'application/json' },
+        payload: { regimenId: 'reg-1', numberOfDays: 14 },
+      });
+
+      expect(res.statusCode).toBe(200);
+      const body = res.json();
+      expect(body.hasShortages).toBe(true);
+      expect(body.canFillCompletely).toBe(false);
+      expect(body.items[0].isShort).toBe(true);
+      expect(body.items[0].shortage).toBe(9);
+    });
+  });
+
+  describe('POST /api/v1/households/:householdId/organizer/fill', () => {
+    it('creates fill and returns 201 with COMPLETED status', async () => {
+      const fill = makeFakeFill({ status: OrganizerFillStatus.COMPLETED });
+      mockFill.mockResolvedValue(fill);
+
+      const res = await app.inject({
+        method: 'POST',
+        url: '/api/v1/households/hh1/organizer/fill',
+        headers: { ...authHeaders, 'content-type': 'application/json' },
+        payload: { regimenId: 'reg-1', numberOfDays: 7, allowPartial: false },
+      });
+
+      expect(res.statusCode).toBe(201);
+      const body = res.json();
+      expect(body._id).toBe('fill-1');
+      expect(body.status).toBe(OrganizerFillStatus.COMPLETED);
+    });
+
+    it('returns 201 with PARTIAL status when wasShort items exist', async () => {
+      const fill = makeFakeFill({
+        status: OrganizerFillStatus.PARTIAL,
+        items: [
+          {
+            medicineId: 'med-1',
+            medicineName: 'Metformin',
+            quantityNeeded: 14,
+            quantityTaken: 5,
+            wasShort: true,
+            shortage: 9,
+            deductions: [{ cabinetItemId: 'ci-1', quantityTaken: 5 }],
+          },
+        ],
+      });
+      mockFill.mockResolvedValue(fill);
+
+      const res = await app.inject({
+        method: 'POST',
+        url: '/api/v1/households/hh1/organizer/fill',
+        headers: { ...authHeaders, 'content-type': 'application/json' },
+        payload: { regimenId: 'reg-1', numberOfDays: 14, allowPartial: true },
+      });
+
+      expect(res.statusCode).toBe(201);
+      const body = res.json();
+      expect(body.status).toBe(OrganizerFillStatus.PARTIAL);
+      expect(body.items[0].wasShort).toBe(true);
+      expect(body.items[0].shortage).toBe(9);
+    });
+
+    it('returns 400 on invalid body (missing regimenId)', async () => {
+      const res = await app.inject({
+        method: 'POST',
+        url: '/api/v1/households/hh1/organizer/fill',
+        headers: { ...authHeaders, 'content-type': 'application/json' },
+        payload: { numberOfDays: 7, allowPartial: false },
+      });
+
+      expect(res.statusCode).toBe(400);
+    });
+
+    it('passes correct args (householdId, userId, body) to service', async () => {
+      const fill = makeFakeFill();
+      mockFill.mockResolvedValue(fill);
+
+      const res = await app.inject({
+        method: 'POST',
+        url: '/api/v1/households/hh1/organizer/fill',
+        headers: { ...authHeaders, 'content-type': 'application/json' },
+        payload: { regimenId: 'reg-1', numberOfDays: 7, allowPartial: false, notes: 'test note' },
+      });
+
+      expect(res.statusCode).toBe(201);
+      expect(mockFill).toHaveBeenCalledWith(
+        'hh1',
+        'kc-1',
+        expect.objectContaining({ regimenId: 'reg-1', numberOfDays: 7, allowPartial: false, notes: 'test note' }),
+      );
+    });
+  });
+
+  describe('POST /api/v1/households/:householdId/organizer/fills/:id/undo', () => {
+    it('reverses fill and returns 200 with REVERSED status', async () => {
+      const fill = makeFakeFill({ status: OrganizerFillStatus.REVERSED });
+      mockUndoFill.mockResolvedValue(fill);
+
+      const res = await app.inject({
+        method: 'POST',
+        url: '/api/v1/households/hh1/organizer/fills/fill-1/undo',
+        headers: authHeaders,
+      });
+
+      expect(res.statusCode).toBe(200);
+      const body = res.json();
+      expect(body._id).toBe('fill-1');
+      expect(body.status).toBe(OrganizerFillStatus.REVERSED);
+    });
+
+    it('passes correct args to service (householdId first, then id, then userId)', async () => {
+      const fill = makeFakeFill({ status: OrganizerFillStatus.REVERSED });
+      mockUndoFill.mockResolvedValue(fill);
+
+      const res = await app.inject({
+        method: 'POST',
+        url: '/api/v1/households/hh1/organizer/fills/fill-42/undo',
+        headers: authHeaders,
+      });
+
+      expect(res.statusCode).toBe(200);
+      expect(mockUndoFill).toHaveBeenCalledWith('hh1', 'fill-42', 'kc-1');
+    });
+  });
+});
diff --git a/packages/api/src/modules/organizer/organizer.routes.ts b/packages/api/src/modules/organizer/organizer.routes.ts
new file mode 100644
index 0000000..b891211
--- /dev/null
+++ b/packages/api/src/modules/organizer/organizer.routes.ts
@@ -0,0 +1,203 @@
+import fp from 'fastify-plugin';
+import { asClass, Lifetime } from 'awilix';
+import type { ZodTypeProvider } from 'fastify-type-provider-zod';
+import { z } from 'zod/v4';
+import {
+  OrganizerPreviewSchema,
+  OrganizerFillSchema,
+  OrganizerFillQuerySchema,
+  OrganizerPreviewResponseSchema,
+  OrganizerFillResponseSchema,
+  OrganizerFillListResponseSchema,
+} from '@meshitrack/shared';
+import { OrganizerRepository } from './organizer.repository.js';
+import { OrganizerService } from './organizer.service.js';
+
+type AnyFillDeduction = {
+  cabinetItemId: string;
+  quantityTaken: number;
+};
+
+type AnyFillItem = {
+  medicineId: string;
+  medicineName: string;
+  quantityNeeded: number;
+  quantityTaken: number;
+  wasShort: boolean;
+  shortage: number;
+  deductions: AnyFillDeduction[];
+};
+
+type AnyFillDoc = {
+  _id: string | { toString: () => string };
+  householdId: string;
+  userId: string;
+  regimenId: string;
+  regimenName: string;
+  numberOfDays: number;
+  fillDate: string | Date | { toISOString: () => string };
+  items: AnyFillItem[];
+  status: string;
+  notes?: string | null;
+  createdAt: string | { toISOString: () => string };
+  updatedAt: string | { toISOString: () => string };
+};
+
+function toStr(v: string | { toString: () => string }): string {
+  return typeof v === 'string' ? v : v.toString();
+}
+
+function toIso(v: string | Date | { toISOString: () => string }): string {
+  if (typeof v === 'string') return v;
+  if (v instanceof Date) return v.toISOString();
+  return v.toISOString();
+}
+
+function toFillResponse(doc: AnyFillDoc) {
+  return {
+    _id: toStr(doc._id),
+    householdId: doc.householdId,
+    userId: doc.userId,
+    regimenId: doc.regimenId,
+    regimenName: doc.regimenName,
+    numberOfDays: doc.numberOfDays,
+    fillDate: toIso(doc.fillDate),
+    items: doc.items.map((item) => ({
+      medicineId: item.medicineId,
+      medicineName: item.medicineName,
+      quantityNeeded: item.quantityNeeded,
+      quantityTaken: item.quantityTaken,
+      wasShort: item.wasShort,
+      shortage: item.shortage,
+      deductions: item.deductions.map((d) => ({
+        cabinetItemId: d.cabinetItemId,
+        quantityTaken: d.quantityTaken,
+      })),
+    })),
+    status: doc.status,
+    ...(doc.notes ? { notes: doc.notes } : {}),
+    createdAt: toIso(doc.createdAt),
+    updatedAt: toIso(doc.updatedAt),
+  };
+}
+
+declare module '@fastify/awilix' {
+  interface Cradle {
+    organizerRepository: OrganizerRepository;
+    organizerService: OrganizerService;
+  }
+}
+
+export default fp(
+  async (fastify) => {
+    fastify.diContainer.register({
+      organizerRepository: asClass(OrganizerRepository, { lifetime: Lifetime.SINGLETON }),
+      organizerService: asClass(OrganizerService, { lifetime: Lifetime.SINGLETON }),
+    });
+
+    const app = fastify.withTypeProvider<ZodTypeProvider>();
+    const householdParams = z.object({ householdId: z.string() });
+
+    // GET /api/v1/households/:householdId/organizer/fills — list fill history
+    app.route({
+      method: 'GET',
+      url: '/api/v1/households/:householdId/organizer/fills',
+      schema: {
+        params: householdParams,
+        querystring: OrganizerFillQuerySchema,
+        response: { 200: OrganizerFillListResponseSchema },
+      },
+      handler: async (request, reply) => {
+        const service = fastify.diContainer.resolve('organizerService');
+        const result = await service.listFills(
+          request.params.householdId,
+          request.user.keycloakId,
+          request.query,
+        );
+        return reply.send({
+          data: result.data.map(toFillResponse),
+          pagination: result.pagination,
+        });
+      },
+    });
+
+    // GET /api/v1/households/:householdId/organizer/fills/:id — get fill details
+    app.route({
+      method: 'GET',
+      url: '/api/v1/households/:householdId/organizer/fills/:id',
+      schema: {
+        params: householdParams.extend({ id: z.string() }),
+        response: { 200: OrganizerFillResponseSchema },
+      },
+      handler: async (request, reply) => {
+        const service = fastify.diContainer.resolve('organizerService');
+        const fill = await service.getFillById(request.params.id, request.params.householdId);
+        return reply.send(toFillResponse(fill));
+      },
+    });
+
+    // POST /api/v1/households/:householdId/organizer/preview — preview fill
+    app.route({
+      method: 'POST',
+      url: '/api/v1/households/:householdId/organizer/preview',
+      schema: {
+        params: householdParams,
+        body: OrganizerPreviewSchema,
+        response: { 200: OrganizerPreviewResponseSchema },
+      },
+      handler: async (request, reply) => {
+        const service = fastify.diContainer.resolve('organizerService');
+        const preview = await service.preview(
+          request.params.householdId,
+          request.user.keycloakId,
+          request.body.regimenId,
+          request.body.numberOfDays,
+        );
+        return reply.send(preview);
+      },
+    });
+
+    // POST /api/v1/households/:householdId/organizer/fill — execute fill
+    app.route({
+      method: 'POST',
+      url: '/api/v1/households/:householdId/organizer/fill',
+      schema: {
+        params: householdParams,
+        body: OrganizerFillSchema,
+        response: { 201: OrganizerFillResponseSchema },
+      },
+      handler: async (request, reply) => {
+        const service = fastify.diContainer.resolve('organizerService');
+        const fill = await service.fill(
+          request.params.householdId,
+          request.user.keycloakId,
+          request.body,
+        );
+        return reply.status(201).send(toFillResponse(fill));
+      },
+    });
+
+    // POST /api/v1/households/:householdId/organizer/fills/:id/undo — reverse fill
+    app.route({
+      method: 'POST',
+      url: '/api/v1/households/:householdId/organizer/fills/:id/undo',
+      schema: {
+        params: householdParams.extend({ id: z.string() }),
+        response: { 200: OrganizerFillResponseSchema },
+      },
+      handler: async (request, reply) => {
+        const service = fastify.diContainer.resolve('organizerService');
+        const fill = await service.undoFill(
+          request.params.householdId,
+          request.params.id,
+          request.user.keycloakId,
+        );
+        return reply.send(toFillResponse(fill));
+      },
+    });
+  },
+  {
+    name: 'organizer-routes',
+    dependencies: ['auth-plugin'],
+  },
+);
diff --git a/packages/api/src/modules/organizer/organizer.service.test.ts b/packages/api/src/modules/organizer/organizer.service.test.ts
new file mode 100644
index 0000000..a921dad
--- /dev/null
+++ b/packages/api/src/modules/organizer/organizer.service.test.ts
@@ -0,0 +1,647 @@
+import { describe, it, expect, vi, beforeEach } from 'vitest';
+import {
+  CabinetEventType,
+  CabinetEventSourceType,
+  OrganizerFillStatus,
+  DosageFrequency,
+} from '@meshitrack/shared';
+
+const { mockSession } = vi.hoisted(() => ({
+  mockSession: {
+    startTransaction: vi.fn(),
+    commitTransaction: vi.fn(),
+    abortTransaction: vi.fn(),
+    endSession: vi.fn(),
+  },
+}));
+
+vi.mock('mongoose', () => {
+  return { default: { startSession: vi.fn().mockResolvedValue(mockSession) } };
+});
+
+import { OrganizerService } from './organizer.service.js';
+
+describe(OrganizerService.name, () => {
+  const mockOrganizerRepo = {
+    findByHousehold: vi.fn(),
+    findById: vi.fn(),
+    create: vi.fn(),
+    updateStatus: vi.fn(),
+  };
+
+  const mockRegimensService = {
+    list: vi.fn(),
+    getById: vi.fn(),
+    create: vi.fn(),
+    update: vi.fn(),
+    delete: vi.fn(),
+    getActiveByUser: vi.fn(),
+    calculateBurnRates: vi.fn(),
+  };
+
+  const mockCabinetRepo = {
+    findByHousehold: vi.fn(),
+    findById: vi.fn(),
+    getAggregateSummary: vi.fn(),
+    create: vi.fn(),
+    update: vi.fn(),
+    adjustQuantity: vi.fn(),
+    findExpiringSoon: vi.fn(),
+    softDelete: vi.fn(),
+    countByMedicineId: vi.fn(),
+    discard: vi.fn(),
+    findActiveByMedicineForFEFO: vi.fn(),
+  };
+
+  const mockCabinetEventsService = {
+    logEvent: vi.fn(),
+    logEvents: vi.fn(),
+    listEvents: vi.fn(),
+    getEventsByItem: vi.fn(),
+    getSpendingSummary: vi.fn(),
+    getAvgUnitPrices: vi.fn(),
+  };
+
+  let service: OrganizerService;
+
+  beforeEach(() => {
+    vi.clearAllMocks();
+    service = new OrganizerService({
+      organizerRepository: mockOrganizerRepo as never,
+      regimensService: mockRegimensService as never,
+      cabinetRepository: mockCabinetRepo as never,
+      cabinetEventsService: mockCabinetEventsService as never,
+    });
+  });
+
+  describe('listFills', () => {
+    it('delegates to repository', async () => {
+      const result = { data: [], pagination: { cursor: null, hasMore: false } };
+      mockOrganizerRepo.findByHousehold.mockResolvedValue(result);
+
+      const response = await service.listFills('hh1', 'user-1', { limit: 20 });
+
+      expect(response).toEqual(result);
+      expect(mockOrganizerRepo.findByHousehold).toHaveBeenCalledWith('hh1', 'user-1', { limit: 20 });
+    });
+  });
+
+  describe('getFillById', () => {
+    it('returns fill when found', async () => {
+      const fill = { _id: 'fill-1', regimenName: 'Morning' };
+      mockOrganizerRepo.findById.mockResolvedValue(fill);
+
+      const result = await service.getFillById('fill-1', 'hh1');
+
+      expect(result).toEqual(fill);
+    });
+
+    it('throws NotFoundError when not found', async () => {
+      mockOrganizerRepo.findById.mockResolvedValue(null);
+
+      await expect(service.getFillById('fill-missing', 'hh1')).rejects.toThrow(
+        'Organizer fill not found',
+      );
+    });
+  });
+
+  describe('preview', () => {
+    const makeRegimen = (overrides = {}) => ({
+      _id: 'reg-1',
+      name: 'Morning Routine',
+      isActive: true,
+      medications: [
+        {
+          medicineId: 'med-1',
+          medicineName: 'Metformin',
+          dosage: 1,
+          frequency: DosageFrequency.DAILY,
+          customFrequencyPerDay: null,
+        },
+      ],
+      ...overrides,
+    });
+
+    it('returns preview with no shortages when stock is sufficient', async () => {
+      mockRegimensService.getById.mockResolvedValue(makeRegimen());
+      mockCabinetRepo.findActiveByMedicineForFEFO.mockResolvedValue([
+        { _id: { toString: () => 'ci-1' }, quantity: 30, expirationDate: new Date('2027-01-01') },
+      ]);
+
+      const result = await service.preview('hh1', 'user-1', 'reg-1', 7);
+
+      expect(result.regimenName).toBe('Morning Routine');
+      expect(result.numberOfDays).toBe(7);
+      expect(result.canFillCompletely).toBe(true);
+      expect(result.hasShortages).toBe(false);
+      expect(result.items).toHaveLength(1);
+      expect(result.items[0].medicineId).toBe('med-1');
+      expect(result.items[0].quantityNeeded).toBe(7);
+      expect(result.items[0].quantityAvailable).toBe(30);
+      expect(result.items[0].isShort).toBe(false);
+      expect(result.items[0].shortage).toBe(0);
+      expect(result.items[0].cabinetBreakdown).toHaveLength(1);
+      expect(result.items[0].cabinetBreakdown[0].quantityToTake).toBe(7);
+      expect(result.items[0].cabinetBreakdown[0].quantityBefore).toBe(30);
+    });
+
+    it('returns preview with shortages when stock is insufficient', async () => {
+      mockRegimensService.getById.mockResolvedValue(makeRegimen());
+      mockCabinetRepo.findActiveByMedicineForFEFO.mockResolvedValue([
+        { _id: { toString: () => 'ci-1' }, quantity: 3, expirationDate: null },
+      ]);
+
+      const result = await service.preview('hh1', 'user-1', 'reg-1', 7);
+
+      expect(result.canFillCompletely).toBe(false);
+      expect(result.hasShortages).toBe(true);
+      expect(result.items[0].isShort).toBe(true);
+      expect(result.items[0].shortage).toBe(4);
+      expect(result.items[0].quantityAvailable).toBe(3);
+    });
+
+    it('handles FEFO allocation across multiple cabinet items', async () => {
+      mockRegimensService.getById.mockResolvedValue(makeRegimen());
+      mockCabinetRepo.findActiveByMedicineForFEFO.mockResolvedValue([
+        { _id: { toString: () => 'ci-1' }, quantity: 3, expirationDate: new Date('2026-06-01') },
+        { _id: { toString: () => 'ci-2' }, quantity: 5, expirationDate: new Date('2026-12-01') },
+      ]);
+
+      const result = await service.preview('hh1', 'user-1', 'reg-1', 7);
+
+      expect(result.canFillCompletely).toBe(true);
+      expect(result.items[0].cabinetBreakdown).toHaveLength(2);
+      expect(result.items[0].cabinetBreakdown[0].cabinetItemId).toBe('ci-1');
+      expect(result.items[0].cabinetBreakdown[0].quantityToTake).toBe(3);
+      expect(result.items[0].cabinetBreakdown[1].cabinetItemId).toBe('ci-2');
+      expect(result.items[0].cabinetBreakdown[1].quantityToTake).toBe(4);
+    });
+
+    it('skips AS_NEEDED medications', async () => {
+      mockRegimensService.getById.mockResolvedValue(
+        makeRegimen({
+          medications: [
+            {
+              medicineId: 'med-1',
+              medicineName: 'Metformin',
+              dosage: 1,
+              frequency: DosageFrequency.AS_NEEDED,
+              customFrequencyPerDay: null,
+            },
+            {
+              medicineId: 'med-2',
+              medicineName: 'Ibuprofen',
+              dosage: 2,
+              frequency: DosageFrequency.DAILY,
+              customFrequencyPerDay: null,
+            },
+          ],
+        }),
+      );
+      mockCabinetRepo.findActiveByMedicineForFEFO.mockResolvedValue([
+        { _id: { toString: () => 'ci-2' }, quantity: 20, expirationDate: null },
+      ]);
+
+      const result = await service.preview('hh1', 'user-1', 'reg-1', 7);
+
+      expect(result.items).toHaveLength(1);
+      expect(result.items[0].medicineId).toBe('med-2');
+    });
+
+    it('throws BadRequestError when regimen is not active', async () => {
+      mockRegimensService.getById.mockResolvedValue(makeRegimen({ isActive: false }));
+
+      await expect(service.preview('hh1', 'user-1', 'reg-1', 7)).rejects.toThrow(
+        'Regimen is not active',
+      );
+    });
+
+    it('handles null expirationDate in cabinet items', async () => {
+      mockRegimensService.getById.mockResolvedValue(makeRegimen());
+      mockCabinetRepo.findActiveByMedicineForFEFO.mockResolvedValue([
+        { _id: { toString: () => 'ci-1' }, quantity: 10, expirationDate: null },
+      ]);
+
+      const result = await service.preview('hh1', 'user-1', 'reg-1', 7);
+
+      expect(result.items[0].cabinetBreakdown[0].expirationDate).toBeNull();
+    });
+
+    it('handles empty cabinet (no items available)', async () => {
+      mockRegimensService.getById.mockResolvedValue(makeRegimen());
+      mockCabinetRepo.findActiveByMedicineForFEFO.mockResolvedValue([]);
+
+      const result = await service.preview('hh1', 'user-1', 'reg-1', 7);
+
+      expect(result.canFillCompletely).toBe(false);
+      expect(result.hasShortages).toBe(true);
+      expect(result.items[0].quantityAvailable).toBe(0);
+      expect(result.items[0].shortage).toBe(7);
+      expect(result.items[0].cabinetBreakdown).toHaveLength(0);
+    });
+
+    it('uses customFrequencyPerDay when present', async () => {
+      mockRegimensService.getById.mockResolvedValue(
+        makeRegimen({
+          medications: [
+            {
+              medicineId: 'med-1',
+              medicineName: 'Custom Med',
+              dosage: 2,
+              frequency: DosageFrequency.CUSTOM,
+              customFrequencyPerDay: 3,
+            },
+          ],
+        }),
+      );
+      mockCabinetRepo.findActiveByMedicineForFEFO.mockResolvedValue([
+        { _id: { toString: () => 'ci-1' }, quantity: 100, expirationDate: null },
+      ]);
+
+      const result = await service.preview('hh1', 'user-1', 'reg-1', 7);
+
+      // dosage(2) * customFrequencyPerDay(3) * numberOfDays(7) = 42
+      expect(result.items[0].quantityNeeded).toBe(42);
+    });
+
+    it('stops taking from cabinet items once remaining is zero', async () => {
+      mockRegimensService.getById.mockResolvedValue(makeRegimen());
+      mockCabinetRepo.findActiveByMedicineForFEFO.mockResolvedValue([
+        { _id: { toString: () => 'ci-1' }, quantity: 7, expirationDate: null },
+        { _id: { toString: () => 'ci-2' }, quantity: 10, expirationDate: null },
+      ]);
+
+      const result = await service.preview('hh1', 'user-1', 'reg-1', 7);
+
+      // Needs 7, first item has 7 -- second item should not be touched
+      expect(result.items[0].cabinetBreakdown).toHaveLength(1);
+      expect(result.items[0].cabinetBreakdown[0].quantityToTake).toBe(7);
+    });
+  });
+
+  describe('fill', () => {
+    const fillInput = {
+      regimenId: 'reg-1',
+      numberOfDays: 7,
+      allowPartial: false,
+      notes: 'Weekly fill',
+    };
+
+    const makeRegimen = () => ({
+      _id: 'reg-1',
+      name: 'Morning Routine',
+      isActive: true,
+      medications: [
+        {
+          medicineId: 'med-1',
+          medicineName: 'Metformin',
+          dosage: 1,
+          frequency: DosageFrequency.DAILY,
+          customFrequencyPerDay: null,
+        },
+      ],
+    });
+
+    it('executes fill successfully with no shortages', async () => {
+      // preview dependencies
+      mockRegimensService.getById.mockResolvedValue(makeRegimen());
+      mockCabinetRepo.findActiveByMedicineForFEFO.mockResolvedValue([
+        { _id: { toString: () => 'ci-1' }, quantity: 30, expirationDate: new Date('2027-01-01') },
+      ]);
+      mockCabinetRepo.adjustQuantity.mockResolvedValue({ _id: 'ci-1', quantity: 23 });
+      mockOrganizerRepo.create.mockResolvedValue({
+        _id: { toString: () => 'fill-1' },
+        householdId: 'hh1',
+        userId: 'user-1',
+        regimenId: 'reg-1',
+        regimenName: 'Morning Routine',
+        status: OrganizerFillStatus.COMPLETED,
+      });
+      mockCabinetEventsService.logEvents.mockResolvedValue([]);
+
+      const result = await service.fill('hh1', 'user-1', fillInput);
+
+      expect(result.status).toBe(OrganizerFillStatus.COMPLETED);
+      expect(mockSession.startTransaction).toHaveBeenCalled();
+      expect(mockSession.commitTransaction).toHaveBeenCalled();
+      expect(mockSession.endSession).toHaveBeenCalled();
+      expect(mockCabinetRepo.adjustQuantity).toHaveBeenCalledWith('ci-1', 'hh1', -7);
+      expect(mockCabinetEventsService.logEvents).toHaveBeenCalled();
+    });
+
+    it('throws BadRequestError when shortages exist and allowPartial is false', async () => {
+      mockRegimensService.getById.mockResolvedValue(makeRegimen());
+      mockCabinetRepo.findActiveByMedicineForFEFO.mockResolvedValue([
+        { _id: { toString: () => 'ci-1' }, quantity: 3, expirationDate: null },
+      ]);
+
+      await expect(service.fill('hh1', 'user-1', fillInput)).rejects.toThrow(
+        'Not enough stock to fill completely',
+      );
+    });
+
+    it('allows partial fill when allowPartial is true', async () => {
+      mockRegimensService.getById.mockResolvedValue(makeRegimen());
+      mockCabinetRepo.findActiveByMedicineForFEFO.mockResolvedValue([
+        { _id: { toString: () => 'ci-1' }, quantity: 3, expirationDate: null },
+      ]);
+      mockCabinetRepo.adjustQuantity.mockResolvedValue({ _id: 'ci-1', quantity: 0 });
+      mockOrganizerRepo.create.mockResolvedValue({
+        _id: { toString: () => 'fill-1' },
+        status: OrganizerFillStatus.PARTIAL,
+      });
+      mockCabinetEventsService.logEvents.mockResolvedValue([]);
+
+      const result = await service.fill('hh1', 'user-1', { ...fillInput, allowPartial: true });
+
+      expect(result.status).toBe(OrganizerFillStatus.PARTIAL);
+      expect(mockOrganizerRepo.create).toHaveBeenCalledWith(
+        expect.objectContaining({
+          status: OrganizerFillStatus.PARTIAL,
+        }),
+      );
+    });
+
+    it('creates CONSUMED events for each deduction', async () => {
+      mockRegimensService.getById.mockResolvedValue(makeRegimen());
+      mockCabinetRepo.findActiveByMedicineForFEFO.mockResolvedValue([
+        { _id: { toString: () => 'ci-1' }, quantity: 30, expirationDate: null },
+      ]);
+      mockCabinetRepo.adjustQuantity.mockResolvedValue({ _id: 'ci-1', quantity: 23 });
+      mockOrganizerRepo.create.mockResolvedValue({
+        _id: { toString: () => 'fill-1' },
+        status: OrganizerFillStatus.COMPLETED,
+      });
+      mockCabinetEventsService.logEvents.mockResolvedValue([]);
+
+      await service.fill('hh1', 'user-1', fillInput);
+
+      const events = mockCabinetEventsService.logEvents.mock.calls[0][0];
+      expect(events).toHaveLength(1);
+      expect(events[0]).toEqual(
+        expect.objectContaining({
+          householdId: 'hh1',
+          userId: 'user-1',
+          cabinetItemId: 'ci-1',
+          medicineId: 'med-1',
+          medicineName: 'Metformin',
+          eventType: CabinetEventType.CONSUMED,
+          quantity: -7,
+          quantityBefore: 30,
+          quantityAfter: 23,
+          sourceType: CabinetEventSourceType.ORGANIZER_FILL,
+          sourceId: 'fill-1',
+        }),
+      );
+    });
+
+    it('handles adjustQuantity returning null (skips deduction)', async () => {
+      mockRegimensService.getById.mockResolvedValue(makeRegimen());
+      mockCabinetRepo.findActiveByMedicineForFEFO.mockResolvedValue([
+        { _id: { toString: () => 'ci-1' }, quantity: 30, expirationDate: null },
+      ]);
+      mockCabinetRepo.adjustQuantity.mockResolvedValue(null);
+      mockOrganizerRepo.create.mockResolvedValue({
+        _id: { toString: () => 'fill-1' },
+        status: OrganizerFillStatus.PARTIAL,
+      });
+      mockCabinetEventsService.logEvents.mockResolvedValue([]);
+
+      const result = await service.fill('hh1', 'user-1', { ...fillInput, allowPartial: true });
+
+      expect(result).toBeTruthy();
+      // No events logged since adjustQuantity returned null
+      const events = mockCabinetEventsService.logEvents.mock.calls[0][0];
+      expect(events).toHaveLength(0);
+    });
+
+    it('aborts transaction and rethrows on error', async () => {
+      mockRegimensService.getById.mockResolvedValue(makeRegimen());
+      mockCabinetRepo.findActiveByMedicineForFEFO.mockResolvedValue([
+        { _id: { toString: () => 'ci-1' }, quantity: 30, expirationDate: null },
+      ]);
+      mockCabinetRepo.adjustQuantity.mockRejectedValue(new Error('DB failure'));
+
+      await expect(service.fill('hh1', 'user-1', fillInput)).rejects.toThrow('DB failure');
+
+      expect(mockSession.abortTransaction).toHaveBeenCalled();
+      expect(mockSession.endSession).toHaveBeenCalled();
+    });
+
+    it('creates fill with notes when provided', async () => {
+      mockRegimensService.getById.mockResolvedValue(makeRegimen());
+      mockCabinetRepo.findActiveByMedicineForFEFO.mockResolvedValue([
+        { _id: { toString: () => 'ci-1' }, quantity: 30, expirationDate: null },
+      ]);
+      mockCabinetRepo.adjustQuantity.mockResolvedValue({ _id: 'ci-1', quantity: 23 });
+      mockOrganizerRepo.create.mockResolvedValue({
+        _id: { toString: () => 'fill-1' },
+        status: OrganizerFillStatus.COMPLETED,
+      });
+      mockCabinetEventsService.logEvents.mockResolvedValue([]);
+
+      await service.fill('hh1', 'user-1', fillInput);
+
+      expect(mockOrganizerRepo.create).toHaveBeenCalledWith(
+        expect.objectContaining({
+          notes: 'Weekly fill',
+        }),
+      );
+    });
+
+    it('sets COMPLETED status when no items have shortages', async () => {
+      mockRegimensService.getById.mockResolvedValue(makeRegimen());
+      mockCabinetRepo.findActiveByMedicineForFEFO.mockResolvedValue([
+        { _id: { toString: () => 'ci-1' }, quantity: 30, expirationDate: null },
+      ]);
+      mockCabinetRepo.adjustQuantity.mockResolvedValue({ _id: 'ci-1', quantity: 23 });
+      mockOrganizerRepo.create.mockResolvedValue({
+        _id: { toString: () => 'fill-1' },
+        status: OrganizerFillStatus.COMPLETED,
+      });
+      mockCabinetEventsService.logEvents.mockResolvedValue([]);
+
+      await service.fill('hh1', 'user-1', fillInput);
+
+      expect(mockOrganizerRepo.create).toHaveBeenCalledWith(
+        expect.objectContaining({
+          status: OrganizerFillStatus.COMPLETED,
+        }),
+      );
+    });
+  });
+
+  describe('undoFill', () => {
+    const makeFill = (overrides = {}) => ({
+      _id: 'fill-1',
+      householdId: 'hh1',
+      userId: 'user-1',
+      status: OrganizerFillStatus.COMPLETED,
+      items: [
+        {
+          medicineId: 'med-1',
+          medicineName: 'Metformin',
+          quantityNeeded: 7,
+          quantityTaken: 7,
+          wasShort: false,
+          shortage: 0,
+          deductions: [{ cabinetItemId: 'ci-1', quantityTaken: 7 }],
+        },
+      ],
+      ...overrides,
+    });
+
+    it('reverses fill and restores quantities', async () => {
+      mockOrganizerRepo.findById.mockResolvedValue(makeFill());
+      mockCabinetRepo.findById.mockResolvedValue({ _id: 'ci-1', quantity: 23 });
+      mockCabinetRepo.adjustQuantity.mockResolvedValue({ _id: 'ci-1', quantity: 30 });
+      mockOrganizerRepo.updateStatus.mockResolvedValue({
+        ...makeFill(),
+        status: OrganizerFillStatus.REVERSED,
+      });
+      mockCabinetEventsService.logEvents.mockResolvedValue([]);
+
+      const result = await service.undoFill('hh1', 'fill-1', 'user-1');
+
+      expect(result.status).toBe(OrganizerFillStatus.REVERSED);
+      expect(mockCabinetRepo.adjustQuantity).toHaveBeenCalledWith('ci-1', 'hh1', 7);
+      expect(mockOrganizerRepo.updateStatus).toHaveBeenCalledWith(
+        'fill-1',
+        'hh1',
+        OrganizerFillStatus.REVERSED,
+      );
+      expect(mockSession.startTransaction).toHaveBeenCalled();
+      expect(mockSession.commitTransaction).toHaveBeenCalled();
+      expect(mockSession.endSession).toHaveBeenCalled();
+    });
+
+    it('creates RESTORED events for each deduction', async () => {
+      mockOrganizerRepo.findById.mockResolvedValue(makeFill());
+      mockCabinetRepo.findById.mockResolvedValue({ _id: 'ci-1', quantity: 23 });
+      mockCabinetRepo.adjustQuantity.mockResolvedValue({ _id: 'ci-1', quantity: 30 });
+      mockOrganizerRepo.updateStatus.mockResolvedValue({
+        ...makeFill(),
+        status: OrganizerFillStatus.REVERSED,
+      });
+      mockCabinetEventsService.logEvents.mockResolvedValue([]);
+
+      await service.undoFill('hh1', 'fill-1', 'user-1');
+
+      const events = mockCabinetEventsService.logEvents.mock.calls[0][0];
+      expect(events).toHaveLength(1);
+      expect(events[0]).toEqual(
+        expect.objectContaining({
+          householdId: 'hh1',
+          userId: 'user-1',
+          cabinetItemId: 'ci-1',
+          medicineId: 'med-1',
+          medicineName: 'Metformin',
+          eventType: CabinetEventType.RESTORED,
+          quantity: 7,
+          quantityBefore: 23,
+          quantityAfter: 30,
+          sourceType: CabinetEventSourceType.ORGANIZER_UNDO,
+          sourceId: 'fill-1',
+        }),
+      );
+    });
+
+    it('throws BadRequestError when fill is already reversed', async () => {
+      mockOrganizerRepo.findById.mockResolvedValue(
+        makeFill({ status: OrganizerFillStatus.REVERSED }),
+      );
+
+      await expect(service.undoFill('hh1', 'fill-1', 'user-1')).rejects.toThrow(
+        'Fill has already been reversed',
+      );
+    });
+
+    it('throws NotFoundError when fill does not exist', async () => {
+      mockOrganizerRepo.findById.mockResolvedValue(null);
+
+      await expect(service.undoFill('hh1', 'fill-missing', 'user-1')).rejects.toThrow(
+        'Organizer fill not found',
+      );
+    });
+
+    it('aborts transaction and rethrows on error', async () => {
+      mockOrganizerRepo.findById.mockResolvedValue(makeFill());
+      mockCabinetRepo.findById.mockResolvedValue({ _id: 'ci-1', quantity: 23 });
+      mockCabinetRepo.adjustQuantity.mockRejectedValue(new Error('DB failure'));
+
+      await expect(service.undoFill('hh1', 'fill-1', 'user-1')).rejects.toThrow('DB failure');
+
+      expect(mockSession.abortTransaction).toHaveBeenCalled();
+      expect(mockSession.endSession).toHaveBeenCalled();
+    });
+
+    it('handles cabinet item not found when restoring (uses 0 as quantityBefore)', async () => {
+      mockOrganizerRepo.findById.mockResolvedValue(makeFill());
+      mockCabinetRepo.findById.mockResolvedValue(null);
+      mockCabinetRepo.adjustQuantity.mockResolvedValue({ _id: 'ci-1', quantity: 7 });
+      mockOrganizerRepo.updateStatus.mockResolvedValue({
+        ...makeFill(),
+        status: OrganizerFillStatus.REVERSED,
+      });
+      mockCabinetEventsService.logEvents.mockResolvedValue([]);
+
+      await service.undoFill('hh1', 'fill-1', 'user-1');
+
+      const events = mockCabinetEventsService.logEvents.mock.calls[0][0];
+      expect(events[0].quantityBefore).toBe(0);
+      expect(events[0].quantityAfter).toBe(7);
+    });
+
+    it('throws NotFoundError when updateStatus returns null', async () => {
+      mockOrganizerRepo.findById.mockResolvedValue(makeFill({ items: [] }));
+      mockOrganizerRepo.updateStatus.mockResolvedValue(null);
+
+      await expect(service.undoFill('hh1', 'fill-1', 'user-1')).rejects.toThrow(
+        'Organizer fill not found',
+      );
+    });
+
+    it('restores multiple deductions across items', async () => {
+      const fill = makeFill({
+        items: [
+          {
+            medicineId: 'med-1',
+            medicineName: 'Metformin',
+            quantityNeeded: 7,
+            quantityTaken: 7,
+            wasShort: false,
+            shortage: 0,
+            deductions: [
+              { cabinetItemId: 'ci-1', quantityTaken: 4 },
+              { cabinetItemId: 'ci-2', quantityTaken: 3 },
+            ],
+          },
+          {
+            medicineId: 'med-2',
+            medicineName: 'Aspirin',
+            quantityNeeded: 14,
+            quantityTaken: 14,
+            wasShort: false,
+            shortage: 0,
+            deductions: [{ cabinetItemId: 'ci-3', quantityTaken: 14 }],
+          },
+        ],
+      });
+      mockOrganizerRepo.findById.mockResolvedValue(fill);
+      mockCabinetRepo.findById.mockResolvedValue({ quantity: 10 });
+      mockCabinetRepo.adjustQuantity.mockResolvedValue({ quantity: 20 });
+      mockOrganizerRepo.updateStatus.mockResolvedValue({
+        ...fill,
+        status: OrganizerFillStatus.REVERSED,
+      });
+      mockCabinetEventsService.logEvents.mockResolvedValue([]);
+
+      await service.undoFill('hh1', 'fill-1', 'user-1');
+
+      expect(mockCabinetRepo.adjustQuantity).toHaveBeenCalledTimes(3);
+      expect(mockCabinetRepo.findById).toHaveBeenCalledTimes(3);
+      const events = mockCabinetEventsService.logEvents.mock.calls[0][0];
+      expect(events).toHaveLength(3);
+    });
+  });
+});
diff --git a/packages/api/src/modules/organizer/organizer.service.ts b/packages/api/src/modules/organizer/organizer.service.ts
new file mode 100644
index 0000000..7f6cf11
--- /dev/null
+++ b/packages/api/src/modules/organizer/organizer.service.ts
@@ -0,0 +1,290 @@
+import mongoose from 'mongoose';
+import type { OrganizerRepository } from './organizer.repository.js';
+import type { RegimensService } from '../regimens/regimens.service.js';
+import type { CabinetRepository } from '../cabinet/cabinet.repository.js';
+import type { CabinetEventsService } from '../cabinet-events/cabinet-events.service.js';
+import type { OrganizerFillInput, OrganizerFillQueryInput } from '@meshitrack/shared';
+import {
+  CabinetEventType,
+  CabinetEventSourceType,
+  OrganizerFillStatus,
+  DosageFrequency,
+  calculateQuantityNeeded,
+} from '@meshitrack/shared';
+import type { CreateCabinetEventData } from '../cabinet-events/cabinet-events.repository.js';
+import { NotFoundError, BadRequestError } from '../../common/errors.js';
+
+interface Deps {
+  organizerRepository: OrganizerRepository;
+  regimensService: RegimensService;
+  cabinetRepository: CabinetRepository;
+  cabinetEventsService: CabinetEventsService;
+}
+
+interface PreviewDeduction {
+  cabinetItemId: string;
+  expirationDate: string | null;
+  quantityToTake: number;
+  quantityBefore: number;
+}
+
+interface PreviewItem {
+  medicineId: string;
+  medicineName: string;
+  quantityNeeded: number;
+  quantityAvailable: number;
+  isShort: boolean;
+  shortage: number;
+  cabinetBreakdown: PreviewDeduction[];
+}
+
+export class OrganizerService {
+  private readonly organizerRepository: OrganizerRepository;
+  private readonly regimensService: RegimensService;
+  private readonly cabinetRepository: CabinetRepository;
+  private readonly cabinetEventsService: CabinetEventsService;
+
+  public constructor({
+    organizerRepository,
+    regimensService,
+    cabinetRepository,
+    cabinetEventsService,
+  }: Deps) {
+    this.organizerRepository = organizerRepository;
+    this.regimensService = regimensService;
+    this.cabinetRepository = cabinetRepository;
+    this.cabinetEventsService = cabinetEventsService;
+  }
+
+  public async listFills(householdId: string, userId: string, query: OrganizerFillQueryInput) {
+    return this.organizerRepository.findByHousehold(householdId, userId, query);
+  }
+
+  public async getFillById(id: string, householdId: string) {
+    const fill = await this.organizerRepository.findById(id, householdId);
+    if (!fill) throw new NotFoundError('Organizer fill not found');
+    return fill;
+  }
+
+  public async preview(householdId: string, userId: string, regimenId: string, numberOfDays: number) {
+    const regimen = await this.regimensService.getById(regimenId, householdId, userId);
+    if (!regimen.isActive) {
+      throw new BadRequestError('Regimen is not active');
+    }
+
+    const items: PreviewItem[] = [];
+    let hasShortages = false;
+
+    for (const med of regimen.medications) {
+      if (med.frequency === DosageFrequency.AS_NEEDED) continue;
+
+      const quantityNeeded = calculateQuantityNeeded(
+        med.dosage,
+        med.frequency as DosageFrequency,
+        numberOfDays,
+        med.customFrequencyPerDay ?? undefined,
+      );
+
+      // Get cabinet items for FEFO allocation
+      const cabinetItems = await this.cabinetRepository.findActiveByMedicineForFEFO(
+        householdId,
+        med.medicineId,
+      );
+
+      let quantityAvailable = 0;
+      const breakdown: PreviewDeduction[] = [];
+      let remaining = quantityNeeded;
+
+      for (const ci of cabinetItems) {
+        if (remaining <= 0) break;
+        const toTake = Math.min(remaining, ci.quantity);
+        quantityAvailable += ci.quantity;
+        breakdown.push({
+          cabinetItemId: ci._id.toString(),
+          expirationDate: ci.expirationDate ? ci.expirationDate.toISOString() : null,
+          quantityToTake: toTake,
+          quantityBefore: ci.quantity,
+        });
+        remaining -= toTake;
+      }
+
+      const isShort = remaining > 0;
+      if (isShort) hasShortages = true;
+
+      items.push({
+        medicineId: med.medicineId,
+        medicineName: med.medicineName,
+        quantityNeeded,
+        quantityAvailable,
+        isShort,
+        shortage: Math.max(0, remaining),
+        cabinetBreakdown: breakdown,
+      });
+    }
+
+    return {
+      regimenName: regimen.name,
+      numberOfDays,
+      items,
+      canFillCompletely: !hasShortages,
+      hasShortages,
+    };
+  }
+
+  public async fill(householdId: string, userId: string, input: OrganizerFillInput) {
+    const previewResult = await this.preview(householdId, userId, input.regimenId, input.numberOfDays);
+
+    if (!input.allowPartial && previewResult.hasShortages) {
+      throw new BadRequestError(
+        'Not enough stock to fill completely. Use allowPartial=true to allow partial fills.',
+      );
+    }
+
+    const regimen = await this.regimensService.getById(input.regimenId, householdId, userId);
+
+    // Execute deductions within a transaction
+    const session = await mongoose.startSession();
+    const events: CreateCabinetEventData[] = [];
+    const fillItems = [];
+
+    try {
+      session.startTransaction();
+
+      for (const previewItem of previewResult.items) {
+        const deductions = [];
+        let totalTaken = 0;
+
+        for (const bd of previewItem.cabinetBreakdown) {
+          const updated = await this.cabinetRepository.adjustQuantity(
+            bd.cabinetItemId,
+            householdId,
+            -bd.quantityToTake,
+          );
+
+          if (updated) {
+            deductions.push({
+              cabinetItemId: bd.cabinetItemId,
+              quantityTaken: bd.quantityToTake,
+            });
+            totalTaken += bd.quantityToTake;
+
+            events.push({
+              householdId,
+              userId,
+              cabinetItemId: bd.cabinetItemId,
+              medicineId: previewItem.medicineId,
+              medicineName: previewItem.medicineName,
+              eventType: CabinetEventType.CONSUMED,
+              quantity: -bd.quantityToTake,
+              quantityBefore: bd.quantityBefore,
+              quantityAfter: bd.quantityBefore - bd.quantityToTake,
+              sourceType: CabinetEventSourceType.ORGANIZER_FILL,
+              sourceId: '', // Will be set after fill is created
+            });
+          }
+        }
+
+        const wasShort = totalTaken < previewItem.quantityNeeded;
+        fillItems.push({
+          medicineId: previewItem.medicineId,
+          medicineName: previewItem.medicineName,
+          quantityNeeded: previewItem.quantityNeeded,
+          quantityTaken: totalTaken,
+          wasShort,
+          shortage: previewItem.quantityNeeded - totalTaken,
+          deductions,
+        });
+      }
+
+      const hasAnyShortage = fillItems.some((fi) => fi.wasShort);
+      const fillRecord = await this.organizerRepository.create({
+        householdId,
+        userId,
+        regimenId: input.regimenId,
+        regimenName: regimen.name,
+        numberOfDays: input.numberOfDays,
+        fillDate: new Date(),
+        items: fillItems,
+        status: hasAnyShortage ? OrganizerFillStatus.PARTIAL : OrganizerFillStatus.COMPLETED,
+        notes: input.notes,
+      });
+
+      await session.commitTransaction();
+
+      // Set sourceId on events and log them
+      const fillId = fillRecord._id.toString();
+      for (const event of events) {
+        event.sourceId = fillId;
+      }
+      await this.cabinetEventsService.logEvents(events);
+
+      return fillRecord;
+    } catch (err) {
+      await session.abortTransaction();
+      throw err;
+    } finally {
+      session.endSession();
+    }
+  }
+
+  public async undoFill(householdId: string, fillId: string, userId: string) {
+    const fill = await this.getFillById(fillId, householdId);
+
+    if (fill.status === OrganizerFillStatus.REVERSED) {
+      throw new BadRequestError('Fill has already been reversed');
+    }
+
+    const session = await mongoose.startSession();
+    const events: CreateCabinetEventData[] = [];
+
+    try {
+      session.startTransaction();
+
+      for (const item of fill.items) {
+        for (const deduction of item.deductions) {
+          // Get current quantity before restoring
+          const current = await this.cabinetRepository.findById(deduction.cabinetItemId, householdId);
+          const quantityBefore = current?.quantity ?? 0;
+
+          await this.cabinetRepository.adjustQuantity(
+            deduction.cabinetItemId,
+            householdId,
+            deduction.quantityTaken,
+          );
+
+          events.push({
+            householdId,
+            userId,
+            cabinetItemId: deduction.cabinetItemId,
+            medicineId: item.medicineId,
+            medicineName: item.medicineName,
+            eventType: CabinetEventType.RESTORED,
+            quantity: deduction.quantityTaken,
+            quantityBefore,
+            quantityAfter: quantityBefore + deduction.quantityTaken,
+            sourceType: CabinetEventSourceType.ORGANIZER_UNDO,
+            sourceId: fillId,
+          });
+        }
+      }
+
+      const updated = await this.organizerRepository.updateStatus(
+        fillId,
+        householdId,
+        OrganizerFillStatus.REVERSED,
+      );
+
+      await session.commitTransaction();
+
+      await this.cabinetEventsService.logEvents(events);
+
+      if (!updated) throw new NotFoundError('Organizer fill not found');
+      return updated;
+    } catch (err) {
+      await session.abortTransaction();
+      throw err;
+    } finally {
+      session.endSession();
+    }
+  }
+}
diff --git a/packages/api/src/modules/regimens/regimens.repository.test.ts b/packages/api/src/modules/regimens/regimens.repository.test.ts
new file mode 100644
index 0000000..6e050d7
--- /dev/null
+++ b/packages/api/src/modules/regimens/regimens.repository.test.ts
@@ -0,0 +1,230 @@
+import { describe, it, expect, vi, beforeEach } from 'vitest';
+
+const { mockFind, mockFindOne, mockFindOneAndUpdate, mockSave } = vi.hoisted(() => ({
+  mockFind: vi.fn(),
+  mockFindOne: vi.fn(),
+  mockFindOneAndUpdate: vi.fn(),
+  mockSave: vi.fn(),
+}));
+
+vi.mock('../../schemas/regimen.schema.js', () => {
+  const chain = () => ({
+    sort: vi.fn().mockReturnThis(),
+    limit: vi.fn().mockReturnThis(),
+    lean: vi.fn().mockReturnThis(),
+    exec: mockFind,
+  });
+
+  const findOneChain = () => ({
+    lean: vi.fn().mockReturnThis(),
+    exec: mockFindOne,
+  });
+
+  const updateChain = () => ({
+    exec: mockFindOneAndUpdate,
+  });
+
+  class FakeModel {
+    data: unknown;
+    constructor(data: unknown) {
+      this.data = data;
+    }
+    save = mockSave;
+    toObject() {
+      return this.data;
+    }
+    static find = vi.fn(() => chain());
+    static findOne = vi.fn(() => findOneChain());
+    static findOneAndUpdate = vi.fn(() => updateChain());
+  }
+
+  return { RegimenModel: FakeModel };
+});
+
+import { RegimensRepository } from './regimens.repository.js';
+
+describe(RegimensRepository.name, () => {
+  let repo: RegimensRepository;
+
+  beforeEach(() => {
+    vi.clearAllMocks();
+    repo = new RegimensRepository();
+  });
+
+  describe('findByHousehold', () => {
+    it('returns paginated items', async () => {
+      const items = [{ _id: 'reg-1', name: 'Morning' }];
+      mockFind.mockResolvedValue(items);
+
+      const result = await repo.findByHousehold('hh1', 'user-1', { limit: 20 });
+
+      expect(result.data).toEqual(items);
+      expect(result.pagination.hasMore).toBe(false);
+    });
+
+    it('handles cursor-based pagination', async () => {
+      const items = [{ _id: 'reg-2', name: 'Evening' }];
+      mockFind.mockResolvedValue(items);
+
+      const cursor = Buffer.from('reg-1').toString('base64');
+      const result = await repo.findByHousehold('hh1', 'user-1', { cursor, limit: 20 });
+
+      expect(result.data).toEqual(items);
+      expect(result.pagination.hasMore).toBe(false);
+    });
+
+    it('sets hasMore when more items exist', async () => {
+      const items = Array.from({ length: 3 }, (_, i) => ({ _id: `reg-${i}`, name: `Reg ${i}` }));
+      mockFind.mockResolvedValue(items);
+
+      const result = await repo.findByHousehold('hh1', 'user-1', { limit: 2 });
+
+      expect(result.data).toHaveLength(2);
+      expect(result.pagination.hasMore).toBe(true);
+      expect(result.pagination.cursor).toBeTruthy();
+    });
+
+    it('returns null cursor when no data', async () => {
+      mockFind.mockResolvedValue([]);
+
+      const result = await repo.findByHousehold('hh1', 'user-1', { limit: 20 });
+
+      expect(result.pagination.cursor).toBeNull();
+      expect(result.pagination.hasMore).toBe(false);
+    });
+
+    it('filters by isActive', async () => {
+      mockFind.mockResolvedValue([]);
+
+      await repo.findByHousehold('hh1', 'user-1', { isActive: true, limit: 20 });
+
+      expect(mockFind).toHaveBeenCalled();
+    });
+
+    it('does not add isActive filter when undefined', async () => {
+      mockFind.mockResolvedValue([]);
+
+      await repo.findByHousehold('hh1', 'user-1', { limit: 20 });
+
+      expect(mockFind).toHaveBeenCalled();
+    });
+
+    it('returns cursor only when hasMore is true', async () => {
+      const items = [{ _id: 'reg-1', name: 'Morning' }];
+      mockFind.mockResolvedValue(items);
+
+      const result = await repo.findByHousehold('hh1', 'user-1', { limit: 20 });
+
+      expect(result.pagination.cursor).toBeNull();
+      expect(result.pagination.hasMore).toBe(false);
+    });
+  });
+
+  describe('findById', () => {
+    it('returns regimen by id, householdId, and userId', async () => {
+      const regimen = { _id: 'reg-1', householdId: 'hh1', userId: 'user-1', name: 'Morning' };
+      mockFindOne.mockResolvedValue(regimen);
+
+      const result = await repo.findById('reg-1', 'hh1', 'user-1');
+
+      expect(result).toEqual(regimen);
+    });
+
+    it('returns null when not found', async () => {
+      mockFindOne.mockResolvedValue(null);
+
+      const result = await repo.findById('reg-missing', 'hh1', 'user-1');
+
+      expect(result).toBeNull();
+    });
+  });
+
+  describe('findActiveByUser', () => {
+    it('returns active regimens for user', async () => {
+      const regimens = [
+        { _id: 'reg-1', isActive: true },
+        { _id: 'reg-2', isActive: true },
+      ];
+      mockFind.mockResolvedValue(regimens);
+
+      const result = await repo.findActiveByUser('hh1', 'user-1');
+
+      expect(result).toEqual(regimens);
+    });
+
+    it('returns empty array when no active regimens', async () => {
+      mockFind.mockResolvedValue([]);
+
+      const result = await repo.findActiveByUser('hh1', 'user-1');
+
+      expect(result).toEqual([]);
+    });
+  });
+
+  describe('create', () => {
+    it('creates and returns regimen', async () => {
+      const data = {
+        name: 'Morning Routine',
+        isActive: true,
+        medications: [
+          {
+            medicineId: 'med-1',
+            medicineName: 'Metformin',
+            medicineStrength: 500,
+            medicineStrengthUnit: 'mg',
+            medicineForm: 'tablet',
+            dosage: 1,
+            dosageUnit: 'tablet',
+            frequency: 'daily',
+          },
+        ],
+      };
+      mockSave.mockImplementation(function (this: { toObject: () => unknown }) {
+        return Promise.resolve(this);
+      });
+
+      const result = await repo.create(data, 'hh1', 'user-1', 'user-1');
+
+      expect(result).toBeTruthy();
+      expect(mockSave).toHaveBeenCalled();
+    });
+  });
+
+  describe('update', () => {
+    it('updates and returns regimen', async () => {
+      const updated = { _id: 'reg-1', name: 'Updated' };
+      mockFindOneAndUpdate.mockResolvedValue(updated);
+
+      const result = await repo.update('reg-1', 'hh1', 'user-1', { name: 'Updated' });
+
+      expect(result).toEqual(updated);
+    });
+
+    it('returns null when regimen not found', async () => {
+      mockFindOneAndUpdate.mockResolvedValue(null);
+
+      const result = await repo.update('reg-missing', 'hh1', 'user-1', { name: 'Updated' });
+
+      expect(result).toBeNull();
+    });
+  });
+
+  describe('softDelete', () => {
+    it('soft deletes and returns regimen', async () => {
+      const deleted = { _id: 'reg-1', isDeleted: true };
+      mockFindOneAndUpdate.mockResolvedValue(deleted);
+
+      const result = await repo.softDelete('reg-1', 'hh1', 'user-1');
+
+      expect(result).toEqual(deleted);
+    });
+
+    it('returns null when regimen not found', async () => {
+      mockFindOneAndUpdate.mockResolvedValue(null);
+
+      const result = await repo.softDelete('reg-missing', 'hh1', 'user-1');
+
+      expect(result).toBeNull();
+    });
+  });
+});
diff --git a/packages/api/src/modules/regimens/regimens.repository.ts b/packages/api/src/modules/regimens/regimens.repository.ts
new file mode 100644
index 0000000..bf7b8f2
--- /dev/null
+++ b/packages/api/src/modules/regimens/regimens.repository.ts
@@ -0,0 +1,92 @@
+import { RegimenModel } from '../../schemas/regimen.schema.js';
+
+interface FindByHouseholdQuery {
+  isActive?: boolean;
+  cursor?: string;
+  limit: number;
+}
+
+interface RegimenMedicationData {
+  medicineId: string;
+  medicineName: string;
+  medicineStrength: number;
+  medicineStrengthUnit: string;
+  medicineForm: string;
+  dosage: number;
+  dosageUnit: string;
+  frequency: string;
+  customFrequencyPerDay?: number;
+  timeOfDay?: string;
+  instructions?: string;
+}
+
+interface CreateRegimenData {
+  name: string;
+  isActive: boolean;
+  medications: RegimenMedicationData[];
+}
+
+interface UpdateRegimenData {
+  name?: string;
+  isActive?: boolean;
+  medications?: RegimenMedicationData[];
+}
+
+export class RegimensRepository {
+  public async findByHousehold(householdId: string, userId: string, query: FindByHouseholdQuery) {
+    const filter: Record<string, unknown> = { householdId, userId, isDeleted: false };
+
+    if (query.isActive !== undefined) filter['isActive'] = query.isActive;
+
+    if (query.cursor) {
+      const id = Buffer.from(query.cursor, 'base64').toString();
+      filter['_id'] = { $gt: id };
+    }
+
+    const limit = query.limit;
+    const items = await RegimenModel.find(filter)
+      .sort({ _id: 1 })
+      .limit(limit + 1)
+      .lean()
+      .exec();
+
+    const hasMore = items.length > limit;
+    const data = hasMore ? items.slice(0, limit) : items;
+    const cursor =
+      data.length > 0 ? Buffer.from(data[data.length - 1]._id.toString()).toString('base64') : null;
+
+    return { data, pagination: { cursor: hasMore ? cursor : null, hasMore } };
+  }
+
+  public async findById(id: string, householdId: string, userId: string) {
+    return RegimenModel.findOne({ _id: id, householdId, userId, isDeleted: false }).lean().exec();
+  }
+
+  public async findActiveByUser(householdId: string, userId: string) {
+    return RegimenModel.find({ householdId, userId, isActive: true, isDeleted: false })
+      .lean()
+      .exec();
+  }
+
+  public async create(data: CreateRegimenData, householdId: string, userId: string, createdBy: string) {
+    const regimen = new RegimenModel({ ...data, householdId, userId, createdBy });
+    const saved = await regimen.save();
+    return saved.toObject();
+  }
+
+  public async update(id: string, householdId: string, userId: string, data: UpdateRegimenData) {
+    return RegimenModel.findOneAndUpdate(
+      { _id: id, householdId, userId, isDeleted: false },
+      { $set: data },
+      { new: true, lean: true },
+    ).exec();
+  }
+
+  public async softDelete(id: string, householdId: string, userId: string) {
+    return RegimenModel.findOneAndUpdate(
+      { _id: id, householdId, userId, isDeleted: false },
+      { $set: { isDeleted: true } },
+      { new: true, lean: true },
+    ).exec();
+  }
+}
diff --git a/packages/api/src/modules/regimens/regimens.routes.test.ts b/packages/api/src/modules/regimens/regimens.routes.test.ts
new file mode 100644
index 0000000..cb6fb38
--- /dev/null
+++ b/packages/api/src/modules/regimens/regimens.routes.test.ts
@@ -0,0 +1,488 @@
+import { describe, it, expect, vi, beforeEach, afterEach } from 'vitest';
+import Fastify from 'fastify';
+import { fastifyAwilixPlugin } from '@fastify/awilix';
+import { serializerCompiler, validatorCompiler } from 'fastify-type-provider-zod';
+import { DosageFrequency, DosageUnit, StrengthUnit, MedicineForm } from '@meshitrack/shared';
+
+vi.mock('jose', () => ({
+  createRemoteJWKSet: vi.fn(() => 'mock-jwks'),
+  jwtVerify: vi.fn().mockResolvedValue({
+    payload: {
+      sub: 'kc-1',
+      email: 'test@example.com',
+      preferred_username: 'testuser',
+      realm_access: { roles: ['member'] },
+      householdIds: ['hh1'],
+    },
+    protectedHeader: { alg: 'RS256' },
+    key: {},
+  }),
+}));
+
+const { mockList, mockGetById, mockCreate, mockUpdate, mockDelete, mockCalculateBurnRates } = vi.hoisted(() => ({
+  mockList: vi.fn(),
+  mockGetById: vi.fn(),
+  mockCreate: vi.fn(),
+  mockUpdate: vi.fn(),
+  mockDelete: vi.fn(),
+  mockCalculateBurnRates: vi.fn(),
+}));
+
+vi.mock('./regimens.repository.js', () => ({
+  RegimensRepository: class {
+    findByHousehold = vi.fn();
+    findById = vi.fn();
+    findActiveByUser = vi.fn();
+    create = vi.fn();
+    update = vi.fn();
+    softDelete = vi.fn();
+    delete = vi.fn();
+  },
+}));
+
+vi.mock('./regimens.service.js', () => ({
+  RegimensService: class {
+    list = mockList;
+    getById = mockGetById;
+    create = mockCreate;
+    update = mockUpdate;
+    delete = mockDelete;
+    getActiveByUser = vi.fn();
+    calculateBurnRates = mockCalculateBurnRates;
+  },
+}));
+
+vi.mock('../users/users.repository.js', () => ({
+  UsersRepository: class {
+    findByKeycloakId = vi.fn().mockResolvedValue({ householdIds: ['hh1'] });
+    upsertFromToken = vi.fn().mockResolvedValue({ householdIds: ['hh1'] });
+  },
+}));
+
+import authPlugin from '../../plugins/auth.plugin.js';
+import householdPlugin from '../../plugins/household.plugin.js';
+import usersRoutes from '../users/users.routes.js';
+import regimensRoutes from './regimens.routes.js';
+
+function makeFakeRegimen(overrides = {}) {
+  return {
+    _id: 'reg-1',
+    householdId: 'hh1',
+    userId: 'kc-1',
+    name: 'Daily Medications',
+    isActive: true,
+    medications: [
+      {
+        medicineId: 'med-1',
+        medicineName: 'Metformin',
+        medicineStrength: 500,
+        medicineStrengthUnit: StrengthUnit.MG,
+        medicineForm: MedicineForm.TABLET,
+        dosage: 1,
+        dosageUnit: DosageUnit.TABLET,
+        frequency: DosageFrequency.DAILY,
+        customFrequencyPerDay: null,
+        timeOfDay: null,
+        instructions: null,
+      },
+    ],
+    createdBy: 'kc-1',
+    createdAt: '2024-06-01T00:00:00.000Z',
+    updatedAt: '2024-06-01T00:00:00.000Z',
+    ...overrides,
+  };
+}
+
+const validPostBody = {
+  name: 'Daily Medications',
+  isActive: true,
+  medications: [
+    {
+      medicineId: 'med-1',
+      dosage: 1,
+      dosageUnit: 'tablet',
+      frequency: 'daily',
+    },
+  ],
+};
+
+describe('regimens.routes', () => {
+  let app: Awaited<ReturnType<typeof buildTestApp>>;
+
+  async function buildTestApp() {
+    const instance = Fastify({ logger: false });
+    instance.setValidatorCompiler(validatorCompiler);
+    instance.setSerializerCompiler(serializerCompiler);
+    await instance.register(fastifyAwilixPlugin, {
+      disposeOnClose: true,
+      disposeOnResponse: true,
+      strictBooleanEnforced: true,
+    });
+    await instance.register(authPlugin);
+    await instance.register(householdPlugin);
+    await instance.register(usersRoutes);
+    await instance.register(regimensRoutes);
+    await instance.ready();
+    return instance;
+  }
+
+  const authHeaders = { authorization: 'Bearer valid-token' };
+
+  beforeEach(async () => {
+    vi.clearAllMocks();
+    app = await buildTestApp();
+  });
+
+  afterEach(async () => {
+    if (app) await app.close();
+  });
+
+  describe('GET /api/v1/households/:householdId/regimens', () => {
+    it('returns paginated list of regimens', async () => {
+      const regimen = makeFakeRegimen();
+      mockList.mockResolvedValue({
+        data: [regimen],
+        pagination: { cursor: null, hasMore: false },
+      });
+
+      const res = await app.inject({
+        method: 'GET',
+        url: '/api/v1/households/hh1/regimens',
+        headers: authHeaders,
+      });
+
+      expect(res.statusCode).toBe(200);
+      const body = res.json();
+      expect(body.data).toHaveLength(1);
+      expect(body.data[0].name).toBe('Daily Medications');
+      expect(body.data[0].isActive).toBe(true);
+      expect(body.pagination.hasMore).toBe(false);
+    });
+
+    it('handles ObjectId and Date objects in response', async () => {
+      const regimen = makeFakeRegimen({
+        _id: { toString: () => 'reg-obj' },
+        createdAt: { toISOString: () => '2024-01-01T00:00:00.000Z' },
+        updatedAt: { toISOString: () => '2024-01-02T00:00:00.000Z' },
+      });
+      mockList.mockResolvedValue({
+        data: [regimen],
+        pagination: { cursor: null, hasMore: false },
+      });
+
+      const res = await app.inject({
+        method: 'GET',
+        url: '/api/v1/households/hh1/regimens',
+        headers: authHeaders,
+      });
+
+      expect(res.statusCode).toBe(200);
+      const body = res.json();
+      expect(body.data[0]._id).toBe('reg-obj');
+      expect(body.data[0].createdAt).toBe('2024-01-01T00:00:00.000Z');
+      expect(body.data[0].updatedAt).toBe('2024-01-02T00:00:00.000Z');
+    });
+
+    it('handles actual Date objects for createdAt/updatedAt', async () => {
+      const regimen = makeFakeRegimen({
+        createdAt: new Date('2024-03-01T00:00:00.000Z'),
+        updatedAt: new Date('2024-03-02T00:00:00.000Z'),
+      });
+      mockList.mockResolvedValue({
+        data: [regimen],
+        pagination: { cursor: null, hasMore: false },
+      });
+
+      const res = await app.inject({
+        method: 'GET',
+        url: '/api/v1/households/hh1/regimens',
+        headers: authHeaders,
+      });
+
+      expect(res.statusCode).toBe(200);
+      const body = res.json();
+      expect(body.data[0].createdAt).toBe('2024-03-01T00:00:00.000Z');
+      expect(body.data[0].updatedAt).toBe('2024-03-02T00:00:00.000Z');
+    });
+
+    it('includes optional medication fields when present', async () => {
+      const regimen = makeFakeRegimen({
+        medications: [
+          {
+            medicineId: 'med-1',
+            medicineName: 'Metformin',
+            medicineStrength: 500,
+            medicineStrengthUnit: StrengthUnit.MG,
+            medicineForm: MedicineForm.TABLET,
+            dosage: 2,
+            dosageUnit: DosageUnit.TABLET,
+            frequency: DosageFrequency.CUSTOM,
+            customFrequencyPerDay: 4,
+            timeOfDay: 'morning',
+            instructions: 'Take with food',
+          },
+        ],
+      });
+      mockList.mockResolvedValue({
+        data: [regimen],
+        pagination: { cursor: null, hasMore: false },
+      });
+
+      const res = await app.inject({
+        method: 'GET',
+        url: '/api/v1/households/hh1/regimens',
+        headers: authHeaders,
+      });
+
+      expect(res.statusCode).toBe(200);
+      const body = res.json();
+      const med = body.data[0].medications[0];
+      expect(med.customFrequencyPerDay).toBe(4);
+      expect(med.timeOfDay).toBe('morning');
+      expect(med.instructions).toBe('Take with food');
+    });
+
+    it('omits null optional medication fields from response', async () => {
+      const regimen = makeFakeRegimen();
+      mockList.mockResolvedValue({
+        data: [regimen],
+        pagination: { cursor: null, hasMore: false },
+      });
+
+      const res = await app.inject({
+        method: 'GET',
+        url: '/api/v1/households/hh1/regimens',
+        headers: authHeaders,
+      });
+
+      expect(res.statusCode).toBe(200);
+      const body = res.json();
+      const med = body.data[0].medications[0];
+      expect(med.customFrequencyPerDay).toBeUndefined();
+      expect(med.timeOfDay).toBeUndefined();
+      expect(med.instructions).toBeUndefined();
+    });
+
+    it('passes query parameters to service', async () => {
+      mockList.mockResolvedValue({
+        data: [],
+        pagination: { cursor: null, hasMore: false },
+      });
+
+      const res = await app.inject({
+        method: 'GET',
+        url: '/api/v1/households/hh1/regimens?isActive=true&limit=5',
+        headers: authHeaders,
+      });
+
+      expect(res.statusCode).toBe(200);
+      expect(mockList).toHaveBeenCalledWith(
+        'hh1',
+        'kc-1',
+        expect.objectContaining({ isActive: true, limit: 5 }),
+      );
+    });
+  });
+
+  describe('GET /api/v1/households/:householdId/regimens/burn-rate', () => {
+    it('returns burn rate data array', async () => {
+      const burnRateItem = {
+        medicineId: 'med-1',
+        medicineName: 'Metformin',
+        dailyConsumption: 1,
+        totalInCabinet: 30,
+        daysUntilEmpty: 30,
+        earliestExpiry: '2025-01-01T00:00:00.000Z',
+        avgUnitPrice: 2.5,
+        projectedDailyCost: 2.5,
+        projectedMonthlyCost: 75,
+        projectedYearlyCost: 912.5,
+        currency: 'USD',
+      };
+      mockCalculateBurnRates.mockResolvedValue([burnRateItem]);
+
+      const res = await app.inject({
+        method: 'GET',
+        url: '/api/v1/households/hh1/regimens/burn-rate',
+        headers: authHeaders,
+      });
+
+      expect(res.statusCode).toBe(200);
+      const body = res.json();
+      expect(body.data).toHaveLength(1);
+      expect(body.data[0].medicineId).toBe('med-1');
+      expect(body.data[0].medicineName).toBe('Metformin');
+      expect(body.data[0].dailyConsumption).toBe(1);
+      expect(body.data[0].daysUntilEmpty).toBe(30);
+      expect(body.data[0].currency).toBe('USD');
+    });
+
+    it('returns empty array when no active regimens', async () => {
+      mockCalculateBurnRates.mockResolvedValue([]);
+
+      const res = await app.inject({
+        method: 'GET',
+        url: '/api/v1/households/hh1/regimens/burn-rate',
+        headers: authHeaders,
+      });
+
+      expect(res.statusCode).toBe(200);
+      const body = res.json();
+      expect(body.data).toHaveLength(0);
+    });
+
+    it('handles null monetary fields correctly', async () => {
+      const burnRateItem = {
+        medicineId: 'med-1',
+        medicineName: 'Metformin',
+        dailyConsumption: 1,
+        totalInCabinet: 30,
+        daysUntilEmpty: 30,
+        earliestExpiry: null,
+        avgUnitPrice: null,
+        projectedDailyCost: null,
+        projectedMonthlyCost: null,
+        projectedYearlyCost: null,
+        currency: null,
+      };
+      mockCalculateBurnRates.mockResolvedValue([burnRateItem]);
+
+      const res = await app.inject({
+        method: 'GET',
+        url: '/api/v1/households/hh1/regimens/burn-rate',
+        headers: authHeaders,
+      });
+
+      expect(res.statusCode).toBe(200);
+      const body = res.json();
+      expect(body.data[0].avgUnitPrice).toBeNull();
+      expect(body.data[0].projectedDailyCost).toBeNull();
+      expect(body.data[0].projectedMonthlyCost).toBeNull();
+      expect(body.data[0].projectedYearlyCost).toBeNull();
+      expect(body.data[0].currency).toBeNull();
+    });
+  });
+
+  describe('GET /api/v1/households/:householdId/regimens/:id', () => {
+    it('returns single regimen by id', async () => {
+      mockGetById.mockResolvedValue(makeFakeRegimen());
+
+      const res = await app.inject({
+        method: 'GET',
+        url: '/api/v1/households/hh1/regimens/reg-1',
+        headers: authHeaders,
+      });
+
+      expect(res.statusCode).toBe(200);
+      const body = res.json();
+      expect(body.name).toBe('Daily Medications');
+      expect(body._id).toBe('reg-1');
+    });
+
+    it('passes id and householdId to service', async () => {
+      mockGetById.mockResolvedValue(makeFakeRegimen());
+
+      await app.inject({
+        method: 'GET',
+        url: '/api/v1/households/hh1/regimens/reg-1',
+        headers: authHeaders,
+      });
+
+      expect(mockGetById).toHaveBeenCalledWith('reg-1', 'hh1', 'kc-1');
+    });
+  });
+
+  describe('POST /api/v1/households/:householdId/regimens', () => {
+    it('creates regimen and returns 201', async () => {
+      mockCreate.mockResolvedValue(makeFakeRegimen());
+
+      const res = await app.inject({
+        method: 'POST',
+        url: '/api/v1/households/hh1/regimens',
+        headers: authHeaders,
+        payload: validPostBody,
+      });
+
+      expect(res.statusCode).toBe(201);
+      const body = res.json();
+      expect(body.name).toBe('Daily Medications');
+      expect(body._id).toBe('reg-1');
+    });
+
+    it('returns 400 on invalid body with empty medications array', async () => {
+      const res = await app.inject({
+        method: 'POST',
+        url: '/api/v1/households/hh1/regimens',
+        headers: authHeaders,
+        payload: { name: 'Bad Regimen', isActive: true, medications: [] },
+      });
+
+      expect(res.statusCode).toBe(400);
+    });
+
+    it('returns 400 on invalid body with missing name', async () => {
+      const res = await app.inject({
+        method: 'POST',
+        url: '/api/v1/households/hh1/regimens',
+        headers: authHeaders,
+        payload: {
+          isActive: true,
+          medications: [
+            {
+              medicineId: 'med-1',
+              dosage: 1,
+              dosageUnit: 'tablet',
+              frequency: 'daily',
+            },
+          ],
+        },
+      });
+
+      expect(res.statusCode).toBe(400);
+    });
+  });
+
+  describe('PATCH /api/v1/households/:householdId/regimens/:id', () => {
+    it('updates regimen and returns 200', async () => {
+      mockUpdate.mockResolvedValue(makeFakeRegimen({ name: 'Updated Regimen' }));
+
+      const res = await app.inject({
+        method: 'PATCH',
+        url: '/api/v1/households/hh1/regimens/reg-1',
+        headers: authHeaders,
+        payload: { name: 'Updated Regimen' },
+      });
+
+      expect(res.statusCode).toBe(200);
+      expect(res.json().name).toBe('Updated Regimen');
+    });
+
+    it('passes id, householdId, and body to service', async () => {
+      mockUpdate.mockResolvedValue(makeFakeRegimen({ isActive: false }));
+
+      await app.inject({
+        method: 'PATCH',
+        url: '/api/v1/households/hh1/regimens/reg-1',
+        headers: authHeaders,
+        payload: { isActive: false },
+      });
+
+      expect(mockUpdate).toHaveBeenCalledWith('reg-1', 'hh1', 'kc-1', expect.objectContaining({ isActive: false }));
+    });
+  });
+
+  describe('DELETE /api/v1/households/:householdId/regimens/:id', () => {
+    it('deletes regimen and returns 204', async () => {
+      mockDelete.mockResolvedValue(undefined);
+
+      const res = await app.inject({
+        method: 'DELETE',
+        url: '/api/v1/households/hh1/regimens/reg-1',
+        headers: authHeaders,
+      });
+
+      expect(res.statusCode).toBe(204);
+      expect(mockDelete).toHaveBeenCalledWith('reg-1', 'hh1', 'kc-1');
+    });
+  });
+});
diff --git a/packages/api/src/modules/regimens/regimens.routes.ts b/packages/api/src/modules/regimens/regimens.routes.ts
new file mode 100644
index 0000000..c34d410
--- /dev/null
+++ b/packages/api/src/modules/regimens/regimens.routes.ts
@@ -0,0 +1,211 @@
+import fp from 'fastify-plugin';
+import { asClass, Lifetime } from 'awilix';
+import type { ZodTypeProvider } from 'fastify-type-provider-zod';
+import { z } from 'zod/v4';
+import {
+  CreateRegimenSchema,
+  UpdateRegimenSchema,
+  RegimenQuerySchema,
+  RegimenResponseSchema,
+  RegimenListResponseSchema,
+  BurnRateResponseSchema,
+} from '@meshitrack/shared';
+import { RegimensRepository } from './regimens.repository.js';
+import { RegimensService } from './regimens.service.js';
+
+type AnyRegimenMedication = {
+  medicineId: string;
+  medicineName: string;
+  medicineStrength: number;
+  medicineStrengthUnit: string;
+  medicineForm: string;
+  dosage: number;
+  dosageUnit: string;
+  frequency: string;
+  customFrequencyPerDay?: number | null;
+  timeOfDay?: string | null;
+  instructions?: string | null;
+};
+
+type AnyRegimenDoc = {
+  _id: string | { toString: () => string };
+  householdId: string;
+  userId: string;
+  name: string;
+  isActive: boolean;
+  medications: AnyRegimenMedication[];
+  createdBy: string;
+  createdAt: string | { toISOString: () => string };
+  updatedAt: string | { toISOString: () => string };
+};
+
+function toStr(v: string | { toString: () => string }): string {
+  return typeof v === 'string' ? v : v.toString();
+}
+
+function toIso(v: string | Date | { toISOString: () => string }): string {
+  if (typeof v === 'string') return v;
+  if (v instanceof Date) return v.toISOString();
+  return v.toISOString();
+}
+
+function toRegimenResponse(doc: AnyRegimenDoc) {
+  return {
+    _id: toStr(doc._id),
+    householdId: doc.householdId,
+    userId: doc.userId,
+    name: doc.name,
+    isActive: doc.isActive,
+    medications: doc.medications.map((med) => ({
+      medicineId: med.medicineId,
+      medicineName: med.medicineName,
+      medicineStrength: med.medicineStrength,
+      medicineStrengthUnit: med.medicineStrengthUnit,
+      medicineForm: med.medicineForm,
+      dosage: med.dosage,
+      dosageUnit: med.dosageUnit,
+      frequency: med.frequency,
+      ...(med.customFrequencyPerDay != null ? { customFrequencyPerDay: med.customFrequencyPerDay } : {}),
+      ...(med.timeOfDay ? { timeOfDay: med.timeOfDay } : {}),
+      ...(med.instructions ? { instructions: med.instructions } : {}),
+    })),
+    createdBy: doc.createdBy,
+    createdAt: toIso(doc.createdAt),
+    updatedAt: toIso(doc.updatedAt),
+  };
+}
+
+declare module '@fastify/awilix' {
+  interface Cradle {
+    regimensRepository: RegimensRepository;
+    regimensService: RegimensService;
+  }
+}
+
+export default fp(
+  async (fastify) => {
+    fastify.diContainer.register({
+      regimensRepository: asClass(RegimensRepository, { lifetime: Lifetime.SINGLETON }),
+      regimensService: asClass(RegimensService, { lifetime: Lifetime.SINGLETON }),
+    });
+
+    const app = fastify.withTypeProvider<ZodTypeProvider>();
+    const householdParams = z.object({ householdId: z.string() });
+
+    // GET /api/v1/households/:householdId/regimens — list user's regimens
+    app.route({
+      method: 'GET',
+      url: '/api/v1/households/:householdId/regimens',
+      schema: {
+        params: householdParams,
+        querystring: RegimenQuerySchema,
+        response: { 200: RegimenListResponseSchema },
+      },
+      handler: async (request, reply) => {
+        const service = fastify.diContainer.resolve('regimensService');
+        const result = await service.list(
+          request.params.householdId,
+          request.user.keycloakId,
+          request.query,
+        );
+        return reply.send({
+          data: result.data.map(toRegimenResponse),
+          pagination: result.pagination,
+        });
+      },
+    });
+
+    // GET /api/v1/households/:householdId/regimens/burn-rate — burn rate + spending projection
+    app.route({
+      method: 'GET',
+      url: '/api/v1/households/:householdId/regimens/burn-rate',
+      schema: {
+        params: householdParams,
+        response: { 200: BurnRateResponseSchema },
+      },
+      handler: async (request, reply) => {
+        const service = fastify.diContainer.resolve('regimensService');
+        const data = await service.calculateBurnRates(
+          request.params.householdId,
+          request.user.keycloakId,
+        );
+        return reply.send({ data });
+      },
+    });
+
+    // GET /api/v1/households/:householdId/regimens/:id — get single regimen
+    app.route({
+      method: 'GET',
+      url: '/api/v1/households/:householdId/regimens/:id',
+      schema: {
+        params: householdParams.extend({ id: z.string() }),
+        response: { 200: RegimenResponseSchema },
+      },
+      handler: async (request, reply) => {
+        const service = fastify.diContainer.resolve('regimensService');
+        const regimen = await service.getById(request.params.id, request.params.householdId, request.user.keycloakId);
+        return reply.send(toRegimenResponse(regimen));
+      },
+    });
+
+    // POST /api/v1/households/:householdId/regimens — create regimen
+    app.route({
+      method: 'POST',
+      url: '/api/v1/households/:householdId/regimens',
+      schema: {
+        params: householdParams,
+        body: CreateRegimenSchema,
+        response: { 201: RegimenResponseSchema },
+      },
+      handler: async (request, reply) => {
+        const service = fastify.diContainer.resolve('regimensService');
+        const regimen = await service.create(
+          request.body,
+          request.params.householdId,
+          request.user.keycloakId,
+        );
+        return reply.status(201).send(toRegimenResponse(regimen));
+      },
+    });
+
+    // PATCH /api/v1/households/:householdId/regimens/:id — update regimen
+    app.route({
+      method: 'PATCH',
+      url: '/api/v1/households/:householdId/regimens/:id',
+      schema: {
+        params: householdParams.extend({ id: z.string() }),
+        body: UpdateRegimenSchema,
+        response: { 200: RegimenResponseSchema },
+      },
+      handler: async (request, reply) => {
+        const service = fastify.diContainer.resolve('regimensService');
+        const regimen = await service.update(
+          request.params.id,
+          request.params.householdId,
+          request.user.keycloakId,
+          request.body,
+        );
+        return reply.send(toRegimenResponse(regimen));
+      },
+    });
+
+    // DELETE /api/v1/households/:householdId/regimens/:id — delete regimen
+    app.route({
+      method: 'DELETE',
+      url: '/api/v1/households/:householdId/regimens/:id',
+      schema: {
+        params: householdParams.extend({ id: z.string() }),
+        response: { 204: z.undefined() },
+      },
+      handler: async (request, reply) => {
+        const service = fastify.diContainer.resolve('regimensService');
+        await service.delete(request.params.id, request.params.householdId, request.user.keycloakId);
+        return reply.status(204).send();
+      },
+    });
+  },
+  {
+    name: 'regimens-routes',
+    dependencies: ['auth-plugin'],
+  },
+);
diff --git a/packages/api/src/modules/regimens/regimens.service.test.ts b/packages/api/src/modules/regimens/regimens.service.test.ts
new file mode 100644
index 0000000..a944e5f
--- /dev/null
+++ b/packages/api/src/modules/regimens/regimens.service.test.ts
@@ -0,0 +1,757 @@
+import { describe, it, expect, vi, beforeEach } from 'vitest';
+import { RegimensService } from './regimens.service.js';
+import { DosageFrequency } from '@meshitrack/shared';
+
+describe(RegimensService.name, () => {
+  const mockRegimensRepo = {
+    findByHousehold: vi.fn(),
+    findById: vi.fn(),
+    findActiveByUser: vi.fn(),
+    create: vi.fn(),
+    update: vi.fn(),
+    softDelete: vi.fn(),
+  };
+
+  const mockMedicinesRepo = {
+    findById: vi.fn(),
+    findByHousehold: vi.fn(),
+    findDuplicate: vi.fn(),
+    create: vi.fn(),
+    update: vi.fn(),
+    softDelete: vi.fn(),
+  };
+
+  const mockCabinetRepo = {
+    findByHousehold: vi.fn(),
+    findById: vi.fn(),
+    getAggregateSummary: vi.fn(),
+    create: vi.fn(),
+    update: vi.fn(),
+    adjustQuantity: vi.fn(),
+    findExpiringSoon: vi.fn(),
+    softDelete: vi.fn(),
+    countByMedicineId: vi.fn(),
+    discard: vi.fn(),
+    findActiveByMedicineForFEFO: vi.fn(),
+  };
+
+  const mockCabinetEventsService = {
+    logEvent: vi.fn(),
+    logEvents: vi.fn(),
+    listEvents: vi.fn(),
+    getEventsByItem: vi.fn(),
+    getSpendingSummary: vi.fn(),
+    getAvgUnitPrices: vi.fn(),
+  };
+
+  let service: RegimensService;
+
+  beforeEach(() => {
+    vi.clearAllMocks();
+    service = new RegimensService({
+      regimensRepository: mockRegimensRepo as never,
+      medicinesRepository: mockMedicinesRepo as never,
+      cabinetRepository: mockCabinetRepo as never,
+      cabinetEventsService: mockCabinetEventsService as never,
+    });
+  });
+
+  describe('list', () => {
+    it('delegates to repository', async () => {
+      const result = { data: [], pagination: { cursor: null, hasMore: false } };
+      mockRegimensRepo.findByHousehold.mockResolvedValue(result);
+
+      const response = await service.list('hh1', 'user-1', { limit: 20 });
+
+      expect(response).toEqual(result);
+      expect(mockRegimensRepo.findByHousehold).toHaveBeenCalledWith('hh1', 'user-1', { limit: 20 });
+    });
+  });
+
+  describe('getById', () => {
+    it('returns regimen when found', async () => {
+      const regimen = { _id: 'reg-1', name: 'Morning' };
+      mockRegimensRepo.findById.mockResolvedValue(regimen);
+
+      const result = await service.getById('reg-1', 'hh1', 'user-1');
+
+      expect(result).toEqual(regimen);
+      expect(mockRegimensRepo.findById).toHaveBeenCalledWith('reg-1', 'hh1', 'user-1');
+    });
+
+    it('throws NotFoundError when not found', async () => {
+      mockRegimensRepo.findById.mockResolvedValue(null);
+
+      await expect(service.getById('reg-missing', 'hh1', 'user-1')).rejects.toThrow('Regimen not found');
+    });
+  });
+
+  describe('create', () => {
+    const createInput = {
+      name: 'Morning Routine',
+      isActive: true,
+      medications: [
+        {
+          medicineId: 'med-1',
+          dosage: 1,
+          dosageUnit: 'tablet' as const,
+          frequency: DosageFrequency.DAILY,
+        },
+      ],
+    };
+
+    it('creates regimen with denormalized medications', async () => {
+      mockMedicinesRepo.findById.mockResolvedValue({
+        _id: 'med-1',
+        name: 'Metformin',
+        strength: 500,
+        strengthUnit: 'mg',
+        form: 'tablet',
+      });
+      const created = { _id: 'reg-1', ...createInput, medications: [{ medicineId: 'med-1', medicineName: 'Metformin' }] };
+      mockRegimensRepo.create.mockResolvedValue(created);
+
+      const result = await service.create(createInput, 'hh1', 'user-1');
+
+      expect(result).toEqual(created);
+      expect(mockRegimensRepo.create).toHaveBeenCalledWith(
+        expect.objectContaining({
+          name: 'Morning Routine',
+          isActive: true,
+          medications: expect.arrayContaining([
+            expect.objectContaining({
+              medicineId: 'med-1',
+              medicineName: 'Metformin',
+              medicineStrength: 500,
+              medicineStrengthUnit: 'mg',
+              medicineForm: 'tablet',
+              dosage: 1,
+              dosageUnit: 'tablet',
+              frequency: DosageFrequency.DAILY,
+            }),
+          ]),
+        }),
+        'hh1',
+        'user-1',
+        'user-1',
+      );
+    });
+
+    it('preserves optional medication fields', async () => {
+      mockMedicinesRepo.findById.mockResolvedValue({
+        _id: 'med-1',
+        name: 'Metformin',
+        strength: 500,
+        strengthUnit: 'mg',
+        form: 'tablet',
+      });
+      mockRegimensRepo.create.mockResolvedValue({ _id: 'reg-1' });
+
+      await service.create(
+        {
+          name: 'Morning',
+          isActive: true,
+          medications: [
+            {
+              medicineId: 'med-1',
+              dosage: 2,
+              dosageUnit: 'tablet' as const,
+              frequency: DosageFrequency.CUSTOM,
+              customFrequencyPerDay: 4,
+              timeOfDay: 'morning' as never,
+              instructions: 'Take with food',
+            },
+          ],
+        },
+        'hh1',
+        'user-1',
+      );
+
+      expect(mockRegimensRepo.create).toHaveBeenCalledWith(
+        expect.objectContaining({
+          medications: expect.arrayContaining([
+            expect.objectContaining({
+              customFrequencyPerDay: 4,
+              timeOfDay: 'morning',
+              instructions: 'Take with food',
+            }),
+          ]),
+        }),
+        'hh1',
+        'user-1',
+        'user-1',
+      );
+    });
+
+    it('throws NotFoundError when medicine not found', async () => {
+      mockMedicinesRepo.findById.mockResolvedValue(null);
+
+      await expect(service.create(createInput, 'hh1', 'user-1')).rejects.toThrow(
+        'Medicine not found: med-1',
+      );
+    });
+
+    it('denormalizes multiple medications', async () => {
+      mockMedicinesRepo.findById
+        .mockResolvedValueOnce({
+          _id: 'med-1',
+          name: 'Metformin',
+          strength: 500,
+          strengthUnit: 'mg',
+          form: 'tablet',
+        })
+        .mockResolvedValueOnce({
+          _id: 'med-2',
+          name: 'Aspirin',
+          strength: 100,
+          strengthUnit: 'mg',
+          form: 'tablet',
+        });
+      mockRegimensRepo.create.mockResolvedValue({ _id: 'reg-1' });
+
+      await service.create(
+        {
+          name: 'Full Routine',
+          isActive: true,
+          medications: [
+            {
+              medicineId: 'med-1',
+              dosage: 1,
+              dosageUnit: 'tablet' as const,
+              frequency: DosageFrequency.DAILY,
+            },
+            {
+              medicineId: 'med-2',
+              dosage: 1,
+              dosageUnit: 'tablet' as const,
+              frequency: DosageFrequency.TWICE_DAILY,
+            },
+          ],
+        },
+        'hh1',
+        'user-1',
+      );
+
+      expect(mockRegimensRepo.create).toHaveBeenCalledWith(
+        expect.objectContaining({
+          medications: expect.arrayContaining([
+            expect.objectContaining({ medicineId: 'med-1', medicineName: 'Metformin' }),
+            expect.objectContaining({ medicineId: 'med-2', medicineName: 'Aspirin' }),
+          ]),
+        }),
+        'hh1',
+        'user-1',
+        'user-1',
+      );
+    });
+  });
+
+  describe('update', () => {
+    it('updates name only', async () => {
+      mockRegimensRepo.findById.mockResolvedValue({ _id: 'reg-1', name: 'Morning' });
+      const updated = { _id: 'reg-1', name: 'Evening' };
+      mockRegimensRepo.update.mockResolvedValue(updated);
+
+      const result = await service.update('reg-1', 'hh1', 'user-1', { name: 'Evening' });
+
+      expect(result).toEqual(updated);
+      expect(mockRegimensRepo.update).toHaveBeenCalledWith('reg-1', 'hh1', 'user-1', { name: 'Evening' });
+    });
+
+    it('updates isActive only', async () => {
+      mockRegimensRepo.findById.mockResolvedValue({ _id: 'reg-1', isActive: true });
+      mockRegimensRepo.update.mockResolvedValue({ _id: 'reg-1', isActive: false });
+
+      await service.update('reg-1', 'hh1', 'user-1', { isActive: false });
+
+      expect(mockRegimensRepo.update).toHaveBeenCalledWith('reg-1', 'hh1', 'user-1', { isActive: false });
+    });
+
+    it('updates medications with denormalization', async () => {
+      mockRegimensRepo.findById.mockResolvedValue({ _id: 'reg-1', name: 'Morning' });
+      mockMedicinesRepo.findById.mockResolvedValue({
+        _id: 'med-1',
+        name: 'Metformin',
+        strength: 500,
+        strengthUnit: 'mg',
+        form: 'tablet',
+      });
+      mockRegimensRepo.update.mockResolvedValue({ _id: 'reg-1' });
+
+      await service.update('reg-1', 'hh1', 'user-1', {
+        medications: [
+          {
+            medicineId: 'med-1',
+            dosage: 2,
+            dosageUnit: 'tablet' as const,
+            frequency: DosageFrequency.DAILY,
+          },
+        ],
+      });
+
+      expect(mockRegimensRepo.update).toHaveBeenCalledWith(
+        'reg-1',
+        'hh1',
+        'user-1',
+        expect.objectContaining({
+          medications: expect.arrayContaining([
+            expect.objectContaining({ medicineName: 'Metformin' }),
+          ]),
+        }),
+      );
+    });
+
+    it('throws NotFoundError when regimen not found on initial lookup', async () => {
+      mockRegimensRepo.findById.mockResolvedValue(null);
+
+      await expect(service.update('reg-missing', 'hh1', 'user-1', { name: 'Updated' })).rejects.toThrow(
+        'Regimen not found',
+      );
+    });
+
+    it('throws NotFoundError when update returns null', async () => {
+      mockRegimensRepo.findById.mockResolvedValue({ _id: 'reg-1', name: 'Morning' });
+      mockRegimensRepo.update.mockResolvedValue(null);
+
+      await expect(service.update('reg-1', 'hh1', 'user-1', { name: 'Updated' })).rejects.toThrow(
+        'Regimen not found',
+      );
+    });
+
+    it('skips undefined fields in updateData', async () => {
+      mockRegimensRepo.findById.mockResolvedValue({ _id: 'reg-1' });
+      mockRegimensRepo.update.mockResolvedValue({ _id: 'reg-1' });
+
+      await service.update('reg-1', 'hh1', 'user-1', {});
+
+      expect(mockRegimensRepo.update).toHaveBeenCalledWith('reg-1', 'hh1', 'user-1', {});
+    });
+
+    it('throws NotFoundError when medicine in medications not found', async () => {
+      mockRegimensRepo.findById.mockResolvedValue({ _id: 'reg-1' });
+      mockMedicinesRepo.findById.mockResolvedValue(null);
+
+      await expect(
+        service.update('reg-1', 'hh1', 'user-1', {
+          medications: [
+            {
+              medicineId: 'med-missing',
+              dosage: 1,
+              dosageUnit: 'tablet' as const,
+              frequency: DosageFrequency.DAILY,
+            },
+          ],
+        }),
+      ).rejects.toThrow('Medicine not found: med-missing');
+    });
+  });
+
+  describe('delete', () => {
+    it('soft deletes regimen', async () => {
+      mockRegimensRepo.findById.mockResolvedValue({ _id: 'reg-1' });
+      mockRegimensRepo.softDelete.mockResolvedValue({ _id: 'reg-1', isDeleted: true });
+
+      const result = await service.delete('reg-1', 'hh1', 'user-1');
+
+      expect(result.isDeleted).toBe(true);
+      expect(mockRegimensRepo.softDelete).toHaveBeenCalledWith('reg-1', 'hh1', 'user-1');
+    });
+
+    it('throws NotFoundError when regimen not found on initial lookup', async () => {
+      mockRegimensRepo.findById.mockResolvedValue(null);
+
+      await expect(service.delete('reg-missing', 'hh1', 'user-1')).rejects.toThrow('Regimen not found');
+    });
+
+    it('throws NotFoundError when softDelete returns null', async () => {
+      mockRegimensRepo.findById.mockResolvedValue({ _id: 'reg-1' });
+      mockRegimensRepo.softDelete.mockResolvedValue(null);
+
+      await expect(service.delete('reg-1', 'hh1', 'user-1')).rejects.toThrow('Regimen not found');
+    });
+  });
+
+  describe('getActiveByUser', () => {
+    it('delegates to repository', async () => {
+      const regimens = [{ _id: 'reg-1', isActive: true }];
+      mockRegimensRepo.findActiveByUser.mockResolvedValue(regimens);
+
+      const result = await service.getActiveByUser('hh1', 'user-1');
+
+      expect(result).toEqual(regimens);
+      expect(mockRegimensRepo.findActiveByUser).toHaveBeenCalledWith('hh1', 'user-1');
+    });
+  });
+
+  describe('calculateBurnRates', () => {
+    it('returns empty array when no active regimens', async () => {
+      mockRegimensRepo.findActiveByUser.mockResolvedValue([]);
+
+      const result = await service.calculateBurnRates('hh1', 'user-1');
+
+      expect(result).toEqual([]);
+    });
+
+    it('returns empty array when regimens have no medications', async () => {
+      mockRegimensRepo.findActiveByUser.mockResolvedValue([{ _id: 'reg-1', medications: [] }]);
+
+      const result = await service.calculateBurnRates('hh1', 'user-1');
+
+      expect(result).toEqual([]);
+    });
+
+    it('calculates burn rates for single medicine', async () => {
+      mockRegimensRepo.findActiveByUser.mockResolvedValue([
+        {
+          _id: 'reg-1',
+          medications: [
+            {
+              medicineId: 'med-1',
+              medicineName: 'Metformin',
+              dosage: 1,
+              frequency: DosageFrequency.DAILY,
+            },
+          ],
+        },
+      ]);
+
+      mockCabinetRepo.getAggregateSummary.mockResolvedValue([
+        { _id: 'med-1', totalQuantity: 30, earliestExpiry: new Date('2026-06-01T00:00:00.000Z') },
+      ]);
+
+      mockCabinetEventsService.getAvgUnitPrices.mockResolvedValue(
+        new Map([['med-1', { avgUnitPrice: 0.5, currency: 'USD' }]]),
+      );
+
+      const result = await service.calculateBurnRates('hh1', 'user-1');
+
+      expect(result).toHaveLength(1);
+      expect(result[0].medicineId).toBe('med-1');
+      expect(result[0].medicineName).toBe('Metformin');
+      expect(result[0].dailyConsumption).toBe(1);
+      expect(result[0].totalInCabinet).toBe(30);
+      expect(result[0].daysUntilEmpty).toBe(30);
+      expect(result[0].earliestExpiry).toBe('2026-06-01T00:00:00.000Z');
+      expect(result[0].avgUnitPrice).toBe(0.5);
+      expect(result[0].projectedDailyCost).toBe(0.5);
+      expect(result[0].projectedMonthlyCost).toBe(15);
+      expect(result[0].projectedYearlyCost).toBe(182.5);
+      expect(result[0].currency).toBe('USD');
+    });
+
+    it('sums daily consumption across multiple regimens', async () => {
+      mockRegimensRepo.findActiveByUser.mockResolvedValue([
+        {
+          _id: 'reg-1',
+          medications: [
+            { medicineId: 'med-1', medicineName: 'Metformin', dosage: 1, frequency: DosageFrequency.DAILY },
+          ],
+        },
+        {
+          _id: 'reg-2',
+          medications: [
+            { medicineId: 'med-1', medicineName: 'Metformin', dosage: 1, frequency: DosageFrequency.TWICE_DAILY },
+          ],
+        },
+      ]);
+
+      mockCabinetRepo.getAggregateSummary.mockResolvedValue([
+        { _id: 'med-1', totalQuantity: 90, earliestExpiry: null },
+      ]);
+
+      mockCabinetEventsService.getAvgUnitPrices.mockResolvedValue(new Map());
+
+      const result = await service.calculateBurnRates('hh1', 'user-1');
+
+      // 1*1 + 1*2 = 3 daily
+      expect(result[0].dailyConsumption).toBe(3);
+      expect(result[0].daysUntilEmpty).toBe(30); // 90 / 3 = 30
+      expect(result[0].earliestExpiry).toBeNull();
+      expect(result[0].avgUnitPrice).toBeNull();
+      expect(result[0].projectedDailyCost).toBeNull();
+      expect(result[0].projectedMonthlyCost).toBeNull();
+      expect(result[0].projectedYearlyCost).toBeNull();
+      expect(result[0].currency).toBeNull();
+    });
+
+    it('handles medicine not in cabinet stock', async () => {
+      mockRegimensRepo.findActiveByUser.mockResolvedValue([
+        {
+          _id: 'reg-1',
+          medications: [
+            { medicineId: 'med-1', medicineName: 'Metformin', dosage: 1, frequency: DosageFrequency.DAILY },
+          ],
+        },
+      ]);
+
+      mockCabinetRepo.getAggregateSummary.mockResolvedValue([]);
+      mockCabinetEventsService.getAvgUnitPrices.mockResolvedValue(new Map());
+
+      const result = await service.calculateBurnRates('hh1', 'user-1');
+
+      expect(result[0].totalInCabinet).toBe(0);
+      expect(result[0].daysUntilEmpty).toBe(0); // Math.floor(0/1) = 0
+    });
+
+    it('excludes AS_NEEDED frequency from burn rate results', async () => {
+      mockRegimensRepo.findActiveByUser.mockResolvedValue([
+        {
+          _id: 'reg-1',
+          medications: [
+            { medicineId: 'med-1', medicineName: 'Ibuprofen', dosage: 1, frequency: DosageFrequency.AS_NEEDED },
+          ],
+        },
+      ]);
+
+      const result = await service.calculateBurnRates('hh1', 'user-1');
+
+      expect(result).toEqual([]);
+    });
+
+    it('handles CUSTOM frequency with customFrequencyPerDay', async () => {
+      mockRegimensRepo.findActiveByUser.mockResolvedValue([
+        {
+          _id: 'reg-1',
+          medications: [
+            {
+              medicineId: 'med-1',
+              medicineName: 'Custom Med',
+              dosage: 2,
+              frequency: DosageFrequency.CUSTOM,
+              customFrequencyPerDay: 3,
+            },
+          ],
+        },
+      ]);
+
+      mockCabinetRepo.getAggregateSummary.mockResolvedValue([
+        { _id: 'med-1', totalQuantity: 60, earliestExpiry: null },
+      ]);
+      mockCabinetEventsService.getAvgUnitPrices.mockResolvedValue(new Map());
+
+      const result = await service.calculateBurnRates('hh1', 'user-1');
+
+      // 2 * 3 = 6 daily
+      expect(result[0].dailyConsumption).toBe(6);
+      expect(result[0].daysUntilEmpty).toBe(10); // 60 / 6 = 10
+    });
+
+    it('excludes CUSTOM frequency without customFrequencyPerDay (zero consumption)', async () => {
+      mockRegimensRepo.findActiveByUser.mockResolvedValue([
+        {
+          _id: 'reg-1',
+          medications: [
+            {
+              medicineId: 'med-1',
+              medicineName: 'Custom Med',
+              dosage: 2,
+              frequency: DosageFrequency.CUSTOM,
+              // no customFrequencyPerDay -> 0 daily consumption -> excluded
+            },
+          ],
+        },
+      ]);
+
+      const result = await service.calculateBurnRates('hh1', 'user-1');
+
+      expect(result).toEqual([]);
+    });
+
+    it('sorts by daysUntilEmpty ascending (most urgent first, nulls last)', async () => {
+      mockRegimensRepo.findActiveByUser.mockResolvedValue([
+        {
+          _id: 'reg-1',
+          medications: [
+            { medicineId: 'med-1', medicineName: 'Med A', dosage: 1, frequency: DosageFrequency.DAILY },
+            { medicineId: 'med-2', medicineName: 'Med B', dosage: 1, frequency: DosageFrequency.DAILY },
+            { medicineId: 'med-3', medicineName: 'Med C', dosage: 1, frequency: DosageFrequency.AS_NEEDED },
+          ],
+        },
+      ]);
+
+      mockCabinetRepo.getAggregateSummary.mockResolvedValue([
+        { _id: 'med-1', totalQuantity: 30, earliestExpiry: null },
+        { _id: 'med-2', totalQuantity: 10, earliestExpiry: null },
+      ]);
+      mockCabinetEventsService.getAvgUnitPrices.mockResolvedValue(new Map());
+
+      const result = await service.calculateBurnRates('hh1', 'user-1');
+
+      // AS_NEEDED (med-3) excluded; med-2: 10 days, med-1: 30 days
+      expect(result).toHaveLength(2);
+      expect(result[0].medicineId).toBe('med-2');
+      expect(result[0].daysUntilEmpty).toBe(10);
+      expect(result[1].medicineId).toBe('med-1');
+      expect(result[1].daysUntilEmpty).toBe(30);
+    });
+
+    it('returns empty array when all medications are AS_NEEDED', async () => {
+      mockRegimensRepo.findActiveByUser.mockResolvedValue([
+        {
+          _id: 'reg-1',
+          medications: [
+            { medicineId: 'med-1', medicineName: 'Med A', dosage: 1, frequency: DosageFrequency.AS_NEEDED },
+            { medicineId: 'med-2', medicineName: 'Med B', dosage: 1, frequency: DosageFrequency.AS_NEEDED },
+          ],
+        },
+      ]);
+
+      const result = await service.calculateBurnRates('hh1', 'user-1');
+
+      expect(result).toEqual([]);
+    });
+
+    it('excludes AS_NEEDED from results even when mixed with scheduled frequencies', async () => {
+      mockRegimensRepo.findActiveByUser.mockResolvedValue([
+        {
+          _id: 'reg-1',
+          medications: [
+            { medicineId: 'med-1', medicineName: 'Med A', dosage: 1, frequency: DosageFrequency.AS_NEEDED },
+            { medicineId: 'med-2', medicineName: 'Med B', dosage: 1, frequency: DosageFrequency.DAILY },
+            { medicineId: 'med-3', medicineName: 'Med C', dosage: 1, frequency: DosageFrequency.DAILY },
+          ],
+        },
+      ]);
+
+      mockCabinetRepo.getAggregateSummary.mockResolvedValue([
+        { _id: 'med-2', totalQuantity: 10, earliestExpiry: null },
+        { _id: 'med-3', totalQuantity: 30, earliestExpiry: null },
+      ]);
+      mockCabinetEventsService.getAvgUnitPrices.mockResolvedValue(new Map());
+
+      const result = await service.calculateBurnRates('hh1', 'user-1');
+
+      // AS_NEEDED (med-1) excluded; med-2: 10 days, med-3: 30 days
+      expect(result).toHaveLength(2);
+      expect(result[0].medicineId).toBe('med-2');
+      expect(result[0].daysUntilEmpty).toBe(10);
+      expect(result[1].medicineId).toBe('med-3');
+      expect(result[1].daysUntilEmpty).toBe(30);
+    });
+
+    it('handles WEEKLY frequency', async () => {
+      mockRegimensRepo.findActiveByUser.mockResolvedValue([
+        {
+          _id: 'reg-1',
+          medications: [
+            { medicineId: 'med-1', medicineName: 'Weekly Med', dosage: 1, frequency: DosageFrequency.WEEKLY },
+          ],
+        },
+      ]);
+
+      mockCabinetRepo.getAggregateSummary.mockResolvedValue([
+        { _id: 'med-1', totalQuantity: 4, earliestExpiry: null },
+      ]);
+      mockCabinetEventsService.getAvgUnitPrices.mockResolvedValue(new Map());
+
+      const result = await service.calculateBurnRates('hh1', 'user-1');
+
+      // 1 * (1/7) ~= 0.1429 daily
+      expect(result[0].dailyConsumption).toBeCloseTo(1 / 7);
+      expect(result[0].daysUntilEmpty).toBe(28); // Math.floor(4 / (1/7)) = 28
+    });
+
+    it('handles EVERY_OTHER_DAY frequency', async () => {
+      mockRegimensRepo.findActiveByUser.mockResolvedValue([
+        {
+          _id: 'reg-1',
+          medications: [
+            { medicineId: 'med-1', medicineName: 'EOD Med', dosage: 1, frequency: DosageFrequency.EVERY_OTHER_DAY },
+          ],
+        },
+      ]);
+
+      mockCabinetRepo.getAggregateSummary.mockResolvedValue([
+        { _id: 'med-1', totalQuantity: 15, earliestExpiry: null },
+      ]);
+      mockCabinetEventsService.getAvgUnitPrices.mockResolvedValue(new Map());
+
+      const result = await service.calculateBurnRates('hh1', 'user-1');
+
+      // 1 * 0.5 = 0.5 daily
+      expect(result[0].dailyConsumption).toBe(0.5);
+      expect(result[0].daysUntilEmpty).toBe(30); // Math.floor(15 / 0.5) = 30
+    });
+
+    it('handles THREE_TIMES_DAILY frequency', async () => {
+      mockRegimensRepo.findActiveByUser.mockResolvedValue([
+        {
+          _id: 'reg-1',
+          medications: [
+            { medicineId: 'med-1', medicineName: 'TID Med', dosage: 1, frequency: DosageFrequency.THREE_TIMES_DAILY },
+          ],
+        },
+      ]);
+
+      mockCabinetRepo.getAggregateSummary.mockResolvedValue([
+        { _id: 'med-1', totalQuantity: 90, earliestExpiry: null },
+      ]);
+      mockCabinetEventsService.getAvgUnitPrices.mockResolvedValue(new Map());
+
+      const result = await service.calculateBurnRates('hh1', 'user-1');
+
+      expect(result[0].dailyConsumption).toBe(3);
+      expect(result[0].daysUntilEmpty).toBe(30); // 90 / 3 = 30
+    });
+
+    it('calculates projected costs correctly', async () => {
+      mockRegimensRepo.findActiveByUser.mockResolvedValue([
+        {
+          _id: 'reg-1',
+          medications: [
+            { medicineId: 'med-1', medicineName: 'Expensive Med', dosage: 2, frequency: DosageFrequency.DAILY },
+          ],
+        },
+      ]);
+
+      mockCabinetRepo.getAggregateSummary.mockResolvedValue([
+        { _id: 'med-1', totalQuantity: 60, earliestExpiry: null },
+      ]);
+      mockCabinetEventsService.getAvgUnitPrices.mockResolvedValue(
+        new Map([['med-1', { avgUnitPrice: 1.5, currency: 'EUR' }]]),
+      );
+
+      const result = await service.calculateBurnRates('hh1', 'user-1');
+
+      // dailyConsumption = 2, avgUnitPrice = 1.5
+      expect(result[0].projectedDailyCost).toBe(3); // 1.5 * 2
+      expect(result[0].projectedMonthlyCost).toBe(90); // 3 * 30
+      expect(result[0].projectedYearlyCost).toBe(1095); // 3 * 365
+      expect(result[0].currency).toBe('EUR');
+    });
+
+    it('handles multiple medicines with different stock and price data', async () => {
+      mockRegimensRepo.findActiveByUser.mockResolvedValue([
+        {
+          _id: 'reg-1',
+          medications: [
+            { medicineId: 'med-1', medicineName: 'Med A', dosage: 1, frequency: DosageFrequency.DAILY },
+            { medicineId: 'med-2', medicineName: 'Med B', dosage: 1, frequency: DosageFrequency.TWICE_DAILY },
+          ],
+        },
+      ]);
+
+      mockCabinetRepo.getAggregateSummary.mockResolvedValue([
+        { _id: 'med-1', totalQuantity: 10, earliestExpiry: new Date('2026-03-01T00:00:00.000Z') },
+        { _id: 'med-2', totalQuantity: 60, earliestExpiry: new Date('2026-12-01T00:00:00.000Z') },
+      ]);
+
+      mockCabinetEventsService.getAvgUnitPrices.mockResolvedValue(
+        new Map([
+          ['med-1', { avgUnitPrice: 2.0, currency: 'USD' }],
+        ]),
+      );
+
+      const result = await service.calculateBurnRates('hh1', 'user-1');
+
+      // med-1: 10 days until empty, med-2: 30 days
+      expect(result[0].medicineId).toBe('med-1');
+      expect(result[0].daysUntilEmpty).toBe(10);
+      expect(result[0].avgUnitPrice).toBe(2.0);
+      expect(result[1].medicineId).toBe('med-2');
+      expect(result[1].daysUntilEmpty).toBe(30);
+      expect(result[1].avgUnitPrice).toBeNull();
+      expect(result[1].currency).toBeNull();
+    });
+  });
+});
diff --git a/packages/api/src/modules/regimens/regimens.service.ts b/packages/api/src/modules/regimens/regimens.service.ts
new file mode 100644
index 0000000..479d910
--- /dev/null
+++ b/packages/api/src/modules/regimens/regimens.service.ts
@@ -0,0 +1,202 @@
+import type { RegimensRepository } from './regimens.repository.js';
+import type { MedicinesRepository } from '../medicines/medicines.repository.js';
+import type { CabinetRepository } from '../cabinet/cabinet.repository.js';
+import type { CabinetEventsService } from '../cabinet-events/cabinet-events.service.js';
+import type { CreateRegimenInput, UpdateRegimenInput, RegimenQueryInput } from '@meshitrack/shared';
+import { getFrequencyMultiplier } from '@meshitrack/shared';
+import type { DosageFrequency } from '@meshitrack/shared';
+import { NotFoundError } from '../../common/errors.js';
+
+interface Deps {
+  regimensRepository: RegimensRepository;
+  medicinesRepository: MedicinesRepository;
+  cabinetRepository: CabinetRepository;
+  cabinetEventsService: CabinetEventsService;
+}
+
+export class RegimensService {
+  private readonly regimensRepository: RegimensRepository;
+  private readonly medicinesRepository: MedicinesRepository;
+  private readonly cabinetRepository: CabinetRepository;
+  private readonly cabinetEventsService: CabinetEventsService;
+
+  public constructor({
+    regimensRepository,
+    medicinesRepository,
+    cabinetRepository,
+    cabinetEventsService,
+  }: Deps) {
+    this.regimensRepository = regimensRepository;
+    this.medicinesRepository = medicinesRepository;
+    this.cabinetRepository = cabinetRepository;
+    this.cabinetEventsService = cabinetEventsService;
+  }
+
+  public async list(householdId: string, userId: string, query: RegimenQueryInput) {
+    return this.regimensRepository.findByHousehold(householdId, userId, query);
+  }
+
+  public async getById(id: string, householdId: string, userId: string) {
+    const regimen = await this.regimensRepository.findById(id, householdId, userId);
+    if (!regimen) throw new NotFoundError('Regimen not found');
+    return regimen;
+  }
+
+  public async create(data: CreateRegimenInput, householdId: string, userId: string) {
+    const medications = await this.denormalizeMedications(data.medications, householdId);
+    return this.regimensRepository.create(
+      { name: data.name, isActive: data.isActive, medications },
+      householdId,
+      userId,
+      userId,
+    );
+  }
+
+  public async update(id: string, householdId: string, userId: string, data: UpdateRegimenInput) {
+    await this.getById(id, householdId, userId);
+
+    const updateData: Record<string, unknown> = {};
+    if (data.name !== undefined) updateData['name'] = data.name;
+    if (data.isActive !== undefined) updateData['isActive'] = data.isActive;
+    if (data.medications !== undefined) {
+      updateData['medications'] = await this.denormalizeMedications(data.medications, householdId);
+    }
+
+    const updated = await this.regimensRepository.update(id, householdId, userId, updateData);
+    if (!updated) throw new NotFoundError('Regimen not found');
+    return updated;
+  }
+
+  public async delete(id: string, householdId: string, userId: string) {
+    await this.getById(id, householdId, userId);
+    const deleted = await this.regimensRepository.softDelete(id, householdId, userId);
+    if (!deleted) throw new NotFoundError('Regimen not found');
+    return deleted;
+  }
+
+  public async getActiveByUser(householdId: string, userId: string) {
+    return this.regimensRepository.findActiveByUser(householdId, userId);
+  }
+
+  public async calculateBurnRates(householdId: string, userId: string) {
+    const regimens = await this.regimensRepository.findActiveByUser(householdId, userId);
+
+    // Sum daily consumption per medicine across all active regimens
+    const consumptionMap = new Map<
+      string,
+      { medicineName: string; dailyConsumption: number }
+    >();
+
+    for (const regimen of regimens) {
+      for (const med of regimen.medications) {
+        const multiplier = getFrequencyMultiplier(
+          med.frequency as DosageFrequency,
+          med.customFrequencyPerDay ?? undefined,
+        );
+        const dailyDose = med.dosage * multiplier;
+        const existing = consumptionMap.get(med.medicineId);
+        if (existing) {
+          existing.dailyConsumption += dailyDose;
+        } else {
+          consumptionMap.set(med.medicineId, {
+            medicineName: med.medicineName,
+            dailyConsumption: dailyDose,
+          });
+        }
+      }
+    }
+
+    // Exclude medicines with zero daily consumption (e.g., AS_NEEDED frequency)
+    for (const [id, consumption] of consumptionMap) {
+      if (consumption.dailyConsumption === 0) consumptionMap.delete(id);
+    }
+
+    if (consumptionMap.size === 0) return [];
+
+    // Get cabinet summary for all medicines in regimens
+    const summaryResults = await this.cabinetRepository.getAggregateSummary(householdId);
+    const stockMap = new Map<
+      string,
+      { totalQuantity: number; earliestExpiry: Date | null }
+    >();
+    for (const s of summaryResults) {
+      stockMap.set(s._id as string, {
+        totalQuantity: s.totalQuantity as number,
+        earliestExpiry: (s.earliestExpiry as Date | null) ?? null,
+      });
+    }
+
+    // Get average unit prices from purchase events
+    const medicineIds = [...consumptionMap.keys()];
+    const priceMap = await this.cabinetEventsService.getAvgUnitPrices(householdId, medicineIds);
+
+    // Build burn rate array
+    const burnRates = [];
+    for (const [medicineId, consumption] of consumptionMap) {
+      const stock = stockMap.get(medicineId);
+      const totalInCabinet = stock?.totalQuantity ?? 0;
+      const earliestExpiry = stock?.earliestExpiry ?? null;
+      const dailyConsumption = consumption.dailyConsumption;
+
+      const daysUntilEmpty =
+        dailyConsumption > 0 ? Math.floor(totalInCabinet / dailyConsumption) : null;
+
+      const priceData = priceMap.get(medicineId);
+      const avgUnitPrice = priceData?.avgUnitPrice ?? null;
+      const currency = priceData?.currency ?? null;
+      const projectedDailyCost =
+        avgUnitPrice !== null && dailyConsumption > 0 ? avgUnitPrice * dailyConsumption : null;
+
+      burnRates.push({
+        medicineId,
+        medicineName: consumption.medicineName,
+        dailyConsumption,
+        totalInCabinet,
+        daysUntilEmpty,
+        earliestExpiry: earliestExpiry ? earliestExpiry.toISOString() : null,
+        avgUnitPrice,
+        projectedDailyCost,
+        projectedMonthlyCost: projectedDailyCost !== null ? projectedDailyCost * 30 : null,
+        projectedYearlyCost: projectedDailyCost !== null ? projectedDailyCost * 365 : null,
+        currency,
+      });
+    }
+
+    // Sort by daysUntilEmpty ASC (most urgent first, nulls last)
+    burnRates.sort((a, b) => {
+      if (a.daysUntilEmpty === null && b.daysUntilEmpty === null) return 0;
+      if (a.daysUntilEmpty === null) return 1;
+      if (b.daysUntilEmpty === null) return -1;
+      return a.daysUntilEmpty - b.daysUntilEmpty;
+    });
+
+    return burnRates;
+  }
+
+  private async denormalizeMedications(
+    medications: CreateRegimenInput['medications'],
+    householdId: string,
+  ) {
+    const result = [];
+    for (const med of medications) {
+      const medicine = await this.medicinesRepository.findById(med.medicineId, householdId);
+      if (!medicine) {
+        throw new NotFoundError(`Medicine not found: ${med.medicineId}`);
+      }
+      result.push({
+        medicineId: med.medicineId,
+        medicineName: medicine.name,
+        medicineStrength: medicine.strength,
+        medicineStrengthUnit: medicine.strengthUnit,
+        medicineForm: medicine.form,
+        dosage: med.dosage,
+        dosageUnit: med.dosageUnit,
+        frequency: med.frequency,
+        customFrequencyPerDay: med.customFrequencyPerDay,
+        timeOfDay: med.timeOfDay,
+        instructions: med.instructions,
+      });
+    }
+    return result;
+  }
+}
diff --git a/packages/api/src/schemas/cabinet-event.schema.ts b/packages/api/src/schemas/cabinet-event.schema.ts
new file mode 100644
index 0000000..c38ad14
--- /dev/null
+++ b/packages/api/src/schemas/cabinet-event.schema.ts
@@ -0,0 +1,40 @@
+import mongoose from 'mongoose';
+import { CabinetEventType, CabinetEventSourceType } from '@meshitrack/shared';
+
+const cabinetEventSchema = new mongoose.Schema(
+  {
+    householdId: { type: String, required: true },
+    userId: { type: String, required: true },
+    cabinetItemId: { type: String, required: true },
+    medicineId: { type: String, required: true },
+    medicineName: { type: String, required: true },
+    eventType: { type: String, enum: Object.values(CabinetEventType), required: true },
+    quantity: { type: Number, required: true },
+    quantityBefore: { type: Number, required: true },
+    quantityAfter: { type: Number, required: true },
+    unitPrice: { type: Number },
+    totalPrice: { type: Number },
+    currency: { type: String },
+    storeId: { type: String },
+    storeName: { type: String },
+    sourceType: { type: String, enum: Object.values(CabinetEventSourceType), required: true },
+    sourceId: { type: String },
+    reason: { type: String },
+    notes: { type: String },
+  },
+  {
+    timestamps: { createdAt: true, updatedAt: false },
+    toJSON: { virtuals: true },
+    toObject: { virtuals: true },
+  },
+);
+
+cabinetEventSchema.index({ householdId: 1, createdAt: -1 });
+cabinetEventSchema.index({ householdId: 1, cabinetItemId: 1, createdAt: -1 });
+cabinetEventSchema.index({ householdId: 1, medicineId: 1, createdAt: -1 });
+cabinetEventSchema.index({ householdId: 1, eventType: 1, createdAt: -1 });
+
+export const CabinetEventModel = mongoose.model('CabinetEvent', cabinetEventSchema);
+export type CabinetEventDocument = mongoose.InferSchemaType<typeof cabinetEventSchema> & {
+  _id: mongoose.Types.ObjectId;
+};
diff --git a/packages/api/src/schemas/cabinet-item.schema.ts b/packages/api/src/schemas/cabinet-item.schema.ts
index 63167b3..26c950d 100644
--- a/packages/api/src/schemas/cabinet-item.schema.ts
+++ b/packages/api/src/schemas/cabinet-item.schema.ts
@@ -22,6 +22,12 @@ const cabinetItemSchema = new mongoose.Schema(
     quantity: { type: Number, required: true, min: 0 },
     unit: { type: String, enum: Object.values(DosageUnit), required: true },
     expirationDate: { type: Date },
+    purchaseDate: { type: Date },
+    unitPrice: { type: Number },
+    totalPrice: { type: Number },
+    currency: { type: String },
+    storeId: { type: String },
+    storeName: { type: String },
     status: {
       type: String,
       enum: Object.values(CabinetItemStatus),
diff --git a/packages/api/src/schemas/organizer-fill.schema.ts b/packages/api/src/schemas/organizer-fill.schema.ts
new file mode 100644
index 0000000..bb6a8c5
--- /dev/null
+++ b/packages/api/src/schemas/organizer-fill.schema.ts
@@ -0,0 +1,55 @@
+import mongoose from 'mongoose';
+import { OrganizerFillStatus } from '@meshitrack/shared';
+
+const organizerDeductionSchema = new mongoose.Schema(
+  {
+    cabinetItemId: { type: String, required: true },
+    quantityTaken: { type: Number, required: true },
+  },
+  { _id: false },
+);
+
+const organizerFillItemSchema = new mongoose.Schema(
+  {
+    medicineId: { type: String, required: true },
+    medicineName: { type: String, required: true },
+    quantityNeeded: { type: Number, required: true },
+    quantityTaken: { type: Number, required: true },
+    wasShort: { type: Boolean, required: true },
+    shortage: { type: Number, required: true },
+    deductions: { type: [organizerDeductionSchema], required: true },
+  },
+  { _id: false },
+);
+
+const organizerFillSchema = new mongoose.Schema(
+  {
+    householdId: { type: String, required: true },
+    userId: { type: String, required: true },
+    regimenId: { type: String, required: true },
+    regimenName: { type: String, required: true },
+    numberOfDays: { type: Number, required: true },
+    fillDate: { type: Date, required: true },
+    items: { type: [organizerFillItemSchema], required: true },
+    status: {
+      type: String,
+      enum: Object.values(OrganizerFillStatus),
+      required: true,
+    },
+    notes: { type: String },
+  },
+  {
+    timestamps: true,
+    toJSON: { virtuals: true },
+    toObject: { virtuals: true },
+  },
+);
+
+organizerFillSchema.index({ householdId: 1, userId: 1, fillDate: -1 });
+organizerFillSchema.index({ householdId: 1, regimenId: 1, fillDate: -1 });
+organizerFillSchema.index({ householdId: 1, status: 1 });
+
+export const OrganizerFillModel = mongoose.model('OrganizerFill', organizerFillSchema);
+export type OrganizerFillDocument = mongoose.InferSchemaType<typeof organizerFillSchema> & {
+  _id: mongoose.Types.ObjectId;
+};
diff --git a/packages/api/src/schemas/regimen.schema.ts b/packages/api/src/schemas/regimen.schema.ts
new file mode 100644
index 0000000..e471a2c
--- /dev/null
+++ b/packages/api/src/schemas/regimen.schema.ts
@@ -0,0 +1,50 @@
+import mongoose from 'mongoose';
+import {
+  DosageFrequency,
+  DosageUnit,
+  MedicineForm,
+  StrengthUnit,
+  TimeOfDay,
+} from '@meshitrack/shared';
+
+const regimenMedicationSchema = new mongoose.Schema(
+  {
+    medicineId: { type: String, required: true },
+    medicineName: { type: String, required: true },
+    medicineStrength: { type: Number, required: true },
+    medicineStrengthUnit: { type: String, enum: Object.values(StrengthUnit), required: true },
+    medicineForm: { type: String, enum: Object.values(MedicineForm), required: true },
+    dosage: { type: Number, required: true },
+    dosageUnit: { type: String, enum: Object.values(DosageUnit), required: true },
+    frequency: { type: String, enum: Object.values(DosageFrequency), required: true },
+    customFrequencyPerDay: { type: Number },
+    timeOfDay: { type: String, enum: Object.values(TimeOfDay) },
+    instructions: { type: String },
+  },
+  { _id: false },
+);
+
+const regimenSchema = new mongoose.Schema(
+  {
+    householdId: { type: String, required: true },
+    userId: { type: String, required: true },
+    name: { type: String, required: true },
+    isActive: { type: Boolean, default: true },
+    medications: { type: [regimenMedicationSchema], required: true },
+    createdBy: { type: String, required: true },
+    isDeleted: { type: Boolean, default: false },
+  },
+  {
+    timestamps: true,
+    toJSON: { virtuals: true },
+    toObject: { virtuals: true },
+  },
+);
+
+regimenSchema.index({ householdId: 1, userId: 1, isActive: 1 });
+regimenSchema.index({ householdId: 1, 'medications.medicineId': 1 });
+
+export const RegimenModel = mongoose.model('Regimen', regimenSchema);
+export type RegimenDocument = mongoose.InferSchemaType<typeof regimenSchema> & {
+  _id: mongoose.Types.ObjectId;
+};
diff --git a/packages/shared/src/enums/cabinet-event.enums.test.ts b/packages/shared/src/enums/cabinet-event.enums.test.ts
new file mode 100644
index 0000000..aca094d
--- /dev/null
+++ b/packages/shared/src/enums/cabinet-event.enums.test.ts
@@ -0,0 +1,39 @@
+import { describe, it, expect } from 'vitest';
+import {
+  CabinetEventType,
+  CabinetEventSourceType,
+} from './cabinet-event.enums.js';
+
+describe(CabinetEventType.name, () => {
+  it('has exactly 6 values', () => {
+    expect(Object.values(CabinetEventType)).toHaveLength(6);
+  });
+
+  it.each([
+    ['PURCHASED', 'purchased'],
+    ['CONSUMED', 'consumed'],
+    ['ADJUSTED', 'adjusted'],
+    ['DISCARDED', 'discarded'],
+    ['RESTORED', 'restored'],
+    ['DELETED', 'deleted'],
+  ])('%s = %s', (key, value) => {
+    expect(CabinetEventType[key as keyof typeof CabinetEventType]).toBe(value);
+  });
+});
+
+describe(CabinetEventSourceType.name, () => {
+  it('has exactly 4 values', () => {
+    expect(Object.values(CabinetEventSourceType)).toHaveLength(4);
+  });
+
+  it.each([
+    ['MANUAL', 'manual'],
+    ['ORGANIZER_FILL', 'organizer_fill'],
+    ['ORGANIZER_UNDO', 'organizer_undo'],
+    ['REFILL_LIST', 'refill_list'],
+  ])('%s = %s', (key, value) => {
+    expect(
+      CabinetEventSourceType[key as keyof typeof CabinetEventSourceType],
+    ).toBe(value);
+  });
+});
diff --git a/packages/shared/src/enums/cabinet-event.enums.ts b/packages/shared/src/enums/cabinet-event.enums.ts
new file mode 100644
index 0000000..428ca77
--- /dev/null
+++ b/packages/shared/src/enums/cabinet-event.enums.ts
@@ -0,0 +1,15 @@
+export enum CabinetEventType {
+  PURCHASED = 'purchased',
+  CONSUMED = 'consumed',
+  ADJUSTED = 'adjusted',
+  DISCARDED = 'discarded',
+  RESTORED = 'restored',
+  DELETED = 'deleted',
+}
+
+export enum CabinetEventSourceType {
+  MANUAL = 'manual',
+  ORGANIZER_FILL = 'organizer_fill',
+  ORGANIZER_UNDO = 'organizer_undo',
+  REFILL_LIST = 'refill_list',
+}
diff --git a/packages/shared/src/enums/index.ts b/packages/shared/src/enums/index.ts
index b0dd95e..e93a5c4 100644
--- a/packages/shared/src/enums/index.ts
+++ b/packages/shared/src/enums/index.ts
@@ -1,3 +1,5 @@
 export * from './roles.enums.js';
 export * from './medicine.enums.js';
 export * from './cabinet.enums.js';
+export * from './cabinet-event.enums.js';
+export * from './regimen.enums.js';
diff --git a/packages/shared/src/enums/regimen.enums.test.ts b/packages/shared/src/enums/regimen.enums.test.ts
new file mode 100644
index 0000000..7b347e7
--- /dev/null
+++ b/packages/shared/src/enums/regimen.enums.test.ts
@@ -0,0 +1,55 @@
+import { describe, it, expect } from 'vitest';
+import {
+  DosageFrequency,
+  TimeOfDay,
+  OrganizerFillStatus,
+} from './regimen.enums.js';
+
+describe(DosageFrequency.name, () => {
+  it('has exactly 7 values', () => {
+    expect(Object.values(DosageFrequency)).toHaveLength(7);
+  });
+
+  it.each([
+    ['DAILY', 'daily'],
+    ['TWICE_DAILY', 'twice_daily'],
+    ['THREE_TIMES_DAILY', 'three_times_daily'],
+    ['WEEKLY', 'weekly'],
+    ['EVERY_OTHER_DAY', 'every_other_day'],
+    ['AS_NEEDED', 'as_needed'],
+    ['CUSTOM', 'custom'],
+  ])('%s = %s', (key, value) => {
+    expect(DosageFrequency[key as keyof typeof DosageFrequency]).toBe(value);
+  });
+});
+
+describe(TimeOfDay.name, () => {
+  it('has exactly 4 values', () => {
+    expect(Object.values(TimeOfDay)).toHaveLength(4);
+  });
+
+  it.each([
+    ['MORNING', 'morning'],
+    ['AFTERNOON', 'afternoon'],
+    ['EVENING', 'evening'],
+    ['BEDTIME', 'bedtime'],
+  ])('%s = %s', (key, value) => {
+    expect(TimeOfDay[key as keyof typeof TimeOfDay]).toBe(value);
+  });
+});
+
+describe(OrganizerFillStatus.name, () => {
+  it('has exactly 3 values', () => {
+    expect(Object.values(OrganizerFillStatus)).toHaveLength(3);
+  });
+
+  it.each([
+    ['COMPLETED', 'completed'],
+    ['PARTIAL', 'partial'],
+    ['REVERSED', 'reversed'],
+  ])('%s = %s', (key, value) => {
+    expect(
+      OrganizerFillStatus[key as keyof typeof OrganizerFillStatus],
+    ).toBe(value);
+  });
+});
diff --git a/packages/shared/src/enums/regimen.enums.ts b/packages/shared/src/enums/regimen.enums.ts
new file mode 100644
index 0000000..7f08065
--- /dev/null
+++ b/packages/shared/src/enums/regimen.enums.ts
@@ -0,0 +1,22 @@
+export enum DosageFrequency {
+  DAILY = 'daily',
+  TWICE_DAILY = 'twice_daily',
+  THREE_TIMES_DAILY = 'three_times_daily',
+  WEEKLY = 'weekly',
+  EVERY_OTHER_DAY = 'every_other_day',
+  AS_NEEDED = 'as_needed',
+  CUSTOM = 'custom',
+}
+
+export enum TimeOfDay {
+  MORNING = 'morning',
+  AFTERNOON = 'afternoon',
+  EVENING = 'evening',
+  BEDTIME = 'bedtime',
+}
+
+export enum OrganizerFillStatus {
+  COMPLETED = 'completed',
+  PARTIAL = 'partial',
+  REVERSED = 'reversed',
+}
diff --git a/packages/shared/src/index.ts b/packages/shared/src/index.ts
index 175c602..e3760c1 100644
--- a/packages/shared/src/index.ts
+++ b/packages/shared/src/index.ts
@@ -6,3 +6,6 @@ export * from './enums/index.js';
 
 // Validation schemas
 export * from './validation/index.js';
+
+// Utils
+export * from './utils/index.js';
diff --git a/packages/shared/src/types/burn-rate.ts b/packages/shared/src/types/burn-rate.ts
new file mode 100644
index 0000000..daf8af7
--- /dev/null
+++ b/packages/shared/src/types/burn-rate.ts
@@ -0,0 +1,13 @@
+export interface BurnRate {
+  medicineId: string;
+  medicineName: string;
+  dailyConsumption: number;
+  totalInCabinet: number;
+  daysUntilEmpty: number | null;
+  earliestExpiry: Date | null;
+  avgUnitPrice: number | null;
+  projectedDailyCost: number | null;
+  projectedMonthlyCost: number | null;
+  projectedYearlyCost: number | null;
+  currency: string | null;
+}
diff --git a/packages/shared/src/types/cabinet-event.ts b/packages/shared/src/types/cabinet-event.ts
new file mode 100644
index 0000000..311b524
--- /dev/null
+++ b/packages/shared/src/types/cabinet-event.ts
@@ -0,0 +1,48 @@
+import type {
+  CabinetEventType,
+  CabinetEventSourceType,
+} from '../enums/cabinet-event.enums.js';
+
+export interface CabinetEvent {
+  id: string;
+  householdId: string;
+  userId: string;
+  cabinetItemId: string;
+  medicineId: string;
+  medicineName: string;
+  eventType: CabinetEventType;
+  quantity: number;
+  quantityBefore: number;
+  quantityAfter: number;
+  unitPrice?: number;
+  totalPrice?: number;
+  currency?: string;
+  storeId?: string;
+  storeName?: string;
+  sourceType: CabinetEventSourceType;
+  sourceId?: string;
+  reason?: string;
+  notes?: string;
+  createdAt: Date;
+}
+
+export interface SpendingSummary {
+  totalSpent: number;
+  currency: string | null;
+  byMedicine: SpendingByMedicine[];
+  byPeriod: SpendingByPeriod[];
+}
+
+export interface SpendingByMedicine {
+  medicineId: string;
+  medicineName: string;
+  totalSpent: number;
+  totalQuantity: number;
+  avgUnitPrice: number;
+  purchaseCount: number;
+}
+
+export interface SpendingByPeriod {
+  period: string;
+  totalSpent: number;
+}
diff --git a/packages/shared/src/types/cabinet.ts b/packages/shared/src/types/cabinet.ts
index ce9284d..9607ed9 100644
--- a/packages/shared/src/types/cabinet.ts
+++ b/packages/shared/src/types/cabinet.ts
@@ -22,6 +22,12 @@ export interface CabinetItem {
   unit: DosageUnit;
   expirationDate?: Date;
   status: CabinetItemStatus;
+  purchaseDate?: Date;
+  unitPrice?: number;
+  totalPrice?: number;
+  currency?: string;
+  storeId?: string;
+  storeName?: string;
   notes?: string;
   createdBy: string;
   createdAt: Date;
diff --git a/packages/shared/src/types/index.ts b/packages/shared/src/types/index.ts
index 0eda0d8..0fb3cee 100644
--- a/packages/shared/src/types/index.ts
+++ b/packages/shared/src/types/index.ts
@@ -3,3 +3,7 @@ export * from './household.js';
 export * from './common.js';
 export * from './medicine.js';
 export * from './cabinet.js';
+export * from './cabinet-event.js';
+export * from './regimen.js';
+export * from './organizer-fill.js';
+export * from './burn-rate.js';
diff --git a/packages/shared/src/types/organizer-fill.ts b/packages/shared/src/types/organizer-fill.ts
new file mode 100644
index 0000000..69a1bc1
--- /dev/null
+++ b/packages/shared/src/types/organizer-fill.ts
@@ -0,0 +1,31 @@
+import type { OrganizerFillStatus } from '../enums/regimen.enums.js';
+
+export interface OrganizerFill {
+  id: string;
+  householdId: string;
+  userId: string;
+  regimenId: string;
+  regimenName: string;
+  numberOfDays: number;
+  fillDate: Date;
+  items: OrganizerFillItem[];
+  status: OrganizerFillStatus;
+  notes?: string;
+  createdAt: Date;
+  updatedAt: Date;
+}
+
+export interface OrganizerFillItem {
+  medicineId: string;
+  medicineName: string;
+  quantityNeeded: number;
+  quantityTaken: number;
+  wasShort: boolean;
+  shortage: number;
+  deductions: OrganizerDeduction[];
+}
+
+export interface OrganizerDeduction {
+  cabinetItemId: string;
+  quantityTaken: number;
+}
diff --git a/packages/shared/src/types/regimen.ts b/packages/shared/src/types/regimen.ts
new file mode 100644
index 0000000..4521bde
--- /dev/null
+++ b/packages/shared/src/types/regimen.ts
@@ -0,0 +1,31 @@
+import type {
+  DosageFrequency,
+  TimeOfDay,
+} from '../enums/regimen.enums.js';
+import type { DosageUnit, MedicineForm, StrengthUnit } from '../enums/medicine.enums.js';
+
+export interface Regimen {
+  id: string;
+  householdId: string;
+  userId: string;
+  name: string;
+  isActive: boolean;
+  medications: RegimenMedication[];
+  createdBy: string;
+  createdAt: Date;
+  updatedAt: Date;
+}
+
+export interface RegimenMedication {
+  medicineId: string;
+  medicineName: string;
+  medicineStrength: number;
+  medicineStrengthUnit: StrengthUnit;
+  medicineForm: MedicineForm;
+  dosage: number;
+  dosageUnit: DosageUnit;
+  frequency: DosageFrequency;
+  customFrequencyPerDay?: number;
+  timeOfDay?: TimeOfDay;
+  instructions?: string;
+}
diff --git a/packages/shared/src/utils/frequency.test.ts b/packages/shared/src/utils/frequency.test.ts
new file mode 100644
index 0000000..6897a04
--- /dev/null
+++ b/packages/shared/src/utils/frequency.test.ts
@@ -0,0 +1,68 @@
+import { describe, it, expect } from 'vitest';
+import { DosageFrequency } from '../enums/regimen.enums.js';
+import { getFrequencyMultiplier, calculateQuantityNeeded } from './frequency.js';
+
+describe('getFrequencyMultiplier', () => {
+  it.each([
+    [DosageFrequency.DAILY, undefined, 1],
+    [DosageFrequency.TWICE_DAILY, undefined, 2],
+    [DosageFrequency.THREE_TIMES_DAILY, undefined, 3],
+    [DosageFrequency.WEEKLY, undefined, 1 / 7],
+    [DosageFrequency.EVERY_OTHER_DAY, undefined, 1 / 2],
+    [DosageFrequency.AS_NEEDED, undefined, 0],
+    [DosageFrequency.CUSTOM, 4, 4],
+    [DosageFrequency.CUSTOM, undefined, 0],
+  ])('%s (customPerDay=%s) = %s', (frequency, custom, expected) => {
+    expect(getFrequencyMultiplier(frequency, custom)).toBe(expected);
+  });
+});
+
+describe('calculateQuantityNeeded', () => {
+  it('daily: 2 pills * 7 days = 14', () => {
+    expect(calculateQuantityNeeded(2, DosageFrequency.DAILY, 7)).toBe(14);
+  });
+
+  it('twice_daily: 1 pill * 2 * 7 days = 14', () => {
+    expect(calculateQuantityNeeded(1, DosageFrequency.TWICE_DAILY, 7)).toBe(14);
+  });
+
+  it('three_times_daily: 1 pill * 3 * 7 days = 21', () => {
+    expect(calculateQuantityNeeded(1, DosageFrequency.THREE_TIMES_DAILY, 7)).toBe(21);
+  });
+
+  it('weekly: 1 pill * ceil(7/7) = 1', () => {
+    expect(calculateQuantityNeeded(1, DosageFrequency.WEEKLY, 7)).toBe(1);
+  });
+
+  it('weekly: 2 pills * ceil(10/7) = 4', () => {
+    expect(calculateQuantityNeeded(2, DosageFrequency.WEEKLY, 10)).toBe(4);
+  });
+
+  it('every_other_day: 1 pill * ceil(7/2) = 4', () => {
+    expect(calculateQuantityNeeded(1, DosageFrequency.EVERY_OTHER_DAY, 7)).toBe(4);
+  });
+
+  it('every_other_day: 1 pill * ceil(6/2) = 3', () => {
+    expect(calculateQuantityNeeded(1, DosageFrequency.EVERY_OTHER_DAY, 6)).toBe(3);
+  });
+
+  it('as_needed: always 0', () => {
+    expect(calculateQuantityNeeded(5, DosageFrequency.AS_NEEDED, 30)).toBe(0);
+  });
+
+  it('custom: 1 pill * 4/day * 7 days = 28', () => {
+    expect(calculateQuantityNeeded(1, DosageFrequency.CUSTOM, 7, 4)).toBe(28);
+  });
+
+  it('custom without customFrequencyPerDay: 0', () => {
+    expect(calculateQuantityNeeded(1, DosageFrequency.CUSTOM, 7)).toBe(0);
+  });
+
+  it('handles fractional dosage: 0.5 pill * 7 days = 3.5', () => {
+    expect(calculateQuantityNeeded(0.5, DosageFrequency.DAILY, 7)).toBe(3.5);
+  });
+
+  it('single day daily: 1 pill', () => {
+    expect(calculateQuantityNeeded(1, DosageFrequency.DAILY, 1)).toBe(1);
+  });
+});
diff --git a/packages/shared/src/utils/frequency.ts b/packages/shared/src/utils/frequency.ts
new file mode 100644
index 0000000..4d857b1
--- /dev/null
+++ b/packages/shared/src/utils/frequency.ts
@@ -0,0 +1,63 @@
+import { DosageFrequency } from '../enums/regimen.enums.js';
+
+/**
+ * Returns the daily frequency multiplier for a given dosage frequency.
+ * For example, TWICE_DAILY returns 2, WEEKLY returns 1/7.
+ * AS_NEEDED returns 0 (excluded from calculations).
+ */
+export function getFrequencyMultiplier(
+  frequency: DosageFrequency,
+  customPerDay?: number,
+): number {
+  switch (frequency) {
+    case DosageFrequency.DAILY:
+      return 1;
+    case DosageFrequency.TWICE_DAILY:
+      return 2;
+    case DosageFrequency.THREE_TIMES_DAILY:
+      return 3;
+    case DosageFrequency.WEEKLY:
+      return 1 / 7;
+    case DosageFrequency.EVERY_OTHER_DAY:
+      return 1 / 2;
+    case DosageFrequency.AS_NEEDED:
+      return 0;
+    case DosageFrequency.CUSTOM:
+      return customPerDay ?? 0;
+  }
+}
+
+/**
+ * Calculate total quantity needed for N days based on dosage and frequency.
+ *
+ * daily:             dosage * numberOfDays
+ * twice_daily:       dosage * 2 * numberOfDays
+ * three_times_daily: dosage * 3 * numberOfDays
+ * weekly:            dosage * ceil(numberOfDays / 7)
+ * every_other_day:   dosage * ceil(numberOfDays / 2)
+ * as_needed:         0 (excluded from organizer fills)
+ * custom:            dosage * customFrequencyPerDay * numberOfDays
+ */
+export function calculateQuantityNeeded(
+  dosage: number,
+  frequency: DosageFrequency,
+  numberOfDays: number,
+  customFrequencyPerDay?: number,
+): number {
+  switch (frequency) {
+    case DosageFrequency.DAILY:
+      return dosage * numberOfDays;
+    case DosageFrequency.TWICE_DAILY:
+      return dosage * 2 * numberOfDays;
+    case DosageFrequency.THREE_TIMES_DAILY:
+      return dosage * 3 * numberOfDays;
+    case DosageFrequency.WEEKLY:
+      return dosage * Math.ceil(numberOfDays / 7);
+    case DosageFrequency.EVERY_OTHER_DAY:
+      return dosage * Math.ceil(numberOfDays / 2);
+    case DosageFrequency.AS_NEEDED:
+      return 0;
+    case DosageFrequency.CUSTOM:
+      return dosage * (customFrequencyPerDay ?? 0) * numberOfDays;
+  }
+}
diff --git a/packages/shared/src/utils/index.ts b/packages/shared/src/utils/index.ts
new file mode 100644
index 0000000..22ca894
--- /dev/null
+++ b/packages/shared/src/utils/index.ts
@@ -0,0 +1 @@
+export * from './frequency.js';
diff --git a/packages/shared/src/validation/cabinet-event.schemas.test.ts b/packages/shared/src/validation/cabinet-event.schemas.test.ts
new file mode 100644
index 0000000..222cda7
--- /dev/null
+++ b/packages/shared/src/validation/cabinet-event.schemas.test.ts
@@ -0,0 +1,111 @@
+import { describe, it, expect } from 'vitest';
+import { CabinetEventType } from '../enums/cabinet-event.enums.js';
+import {
+  CabinetEventQuerySchema,
+  SpendingSummaryQuerySchema,
+  DiscardCabinetItemSchema,
+} from './cabinet-event.schemas.js';
+
+describe('CabinetEventQuerySchema', () => {
+  it('applies default limit', () => {
+    const result = CabinetEventQuerySchema.safeParse({});
+    expect(result.success).toBe(true);
+    if (result.success) {
+      expect(result.data.limit).toBe(20);
+    }
+  });
+
+  it('accepts all filters', () => {
+    const result = CabinetEventQuerySchema.safeParse({
+      medicineId: 'med-1',
+      eventType: CabinetEventType.PURCHASED,
+      startDate: '2026-01-01T00:00:00.000Z',
+      endDate: '2026-12-31T00:00:00.000Z',
+      cursor: 'abc',
+      limit: 50,
+    });
+    expect(result.success).toBe(true);
+  });
+
+  it('rejects invalid eventType', () => {
+    const result = CabinetEventQuerySchema.safeParse({ eventType: 'invalid' });
+    expect(result.success).toBe(false);
+  });
+
+  it('rejects limit over 100', () => {
+    const result = CabinetEventQuerySchema.safeParse({ limit: 101 });
+    expect(result.success).toBe(false);
+  });
+});
+
+describe('SpendingSummaryQuerySchema', () => {
+  it('defaults period to month', () => {
+    const result = SpendingSummaryQuerySchema.safeParse({});
+    expect(result.success).toBe(true);
+    if (result.success) {
+      expect(result.data.period).toBe('month');
+    }
+  });
+
+  it('accepts quarter period', () => {
+    const result = SpendingSummaryQuerySchema.safeParse({ period: 'quarter' });
+    expect(result.success).toBe(true);
+  });
+
+  it('accepts year period', () => {
+    const result = SpendingSummaryQuerySchema.safeParse({ period: 'year' });
+    expect(result.success).toBe(true);
+  });
+
+  it('rejects invalid period', () => {
+    const result = SpendingSummaryQuerySchema.safeParse({ period: 'week' });
+    expect(result.success).toBe(false);
+  });
+
+  it('accepts optional medicineId and date range', () => {
+    const result = SpendingSummaryQuerySchema.safeParse({
+      medicineId: 'med-1',
+      startDate: '2026-01-01T00:00:00.000Z',
+      endDate: '2026-06-30T00:00:00.000Z',
+    });
+    expect(result.success).toBe(true);
+  });
+});
+
+describe('DiscardCabinetItemSchema', () => {
+  it('accepts valid input', () => {
+    const result = DiscardCabinetItemSchema.safeParse({
+      reason: 'expired',
+      notes: 'Found during cleanup',
+    });
+    expect(result.success).toBe(true);
+  });
+
+  it('accepts reason only', () => {
+    const result = DiscardCabinetItemSchema.safeParse({ reason: 'damaged' });
+    expect(result.success).toBe(true);
+  });
+
+  it('rejects empty reason', () => {
+    const result = DiscardCabinetItemSchema.safeParse({ reason: '' });
+    expect(result.success).toBe(false);
+  });
+
+  it('rejects missing reason', () => {
+    const result = DiscardCabinetItemSchema.safeParse({});
+    expect(result.success).toBe(false);
+  });
+
+  it('trims reason', () => {
+    const result = DiscardCabinetItemSchema.safeParse({ reason: '  expired  ' });
+    expect(result.success).toBe(true);
+    if (result.success) {
+      expect(result.data.reason).toBe('expired');
+    }
+  });
+
+  it('rejects reason over 500 chars', () => {
+    const result = DiscardCabinetItemSchema.safeParse({ reason: 'x'.repeat(501) });
+    expect(result.success).toBe(false);
+  });
+});
diff --git a/packages/shared/src/validation/cabinet-event.schemas.ts b/packages/shared/src/validation/cabinet-event.schemas.ts
new file mode 100644
index 0000000..6e111be
--- /dev/null
+++ b/packages/shared/src/validation/cabinet-event.schemas.ts
@@ -0,0 +1,87 @@
+import { z } from 'zod/v4';
+import { CabinetEventType } from '../enums/cabinet-event.enums.js';
+
+// --- Query ---
+
+export const CabinetEventQuerySchema = z.object({
+  medicineId: z.string().optional(),
+  eventType: z.nativeEnum(CabinetEventType).optional(),
+  startDate: z.iso.datetime().optional(),
+  endDate: z.iso.datetime().optional(),
+  cursor: z.string().optional(),
+  limit: z.coerce.number().int().min(1).max(100).default(20),
+});
+
+export const SpendingSummaryQuerySchema = z.object({
+  period: z.enum(['month', 'quarter', 'year']).default('month'),
+  medicineId: z.string().optional(),
+  startDate: z.iso.datetime().optional(),
+  endDate: z.iso.datetime().optional(),
+});
+
+// --- Discard ---
+
+export const DiscardCabinetItemSchema = z.object({
+  reason: z.string().min(1).max(500).trim(),
+  notes: z.string().max(1000).trim().optional(),
+});
+
+// --- Response ---
+
+export const CabinetEventResponseSchema = z.object({
+  _id: z.string(),
+  householdId: z.string(),
+  userId: z.string(),
+  cabinetItemId: z.string(),
+  medicineId: z.string(),
+  medicineName: z.string(),
+  eventType: z.string(),
+  quantity: z.number(),
+  quantityBefore: z.number(),
+  quantityAfter: z.number(),
+  unitPrice: z.number().optional(),
+  totalPrice: z.number().optional(),
+  currency: z.string().optional(),
+  storeId: z.string().optional(),
+  storeName: z.string().optional(),
+  sourceType: z.string(),
+  sourceId: z.string().optional(),
+  reason: z.string().optional(),
+  notes: z.string().optional(),
+  createdAt: z.string(),
+});
+
+export const CabinetEventListResponseSchema = z.object({
+  data: z.array(CabinetEventResponseSchema),
+  pagination: z.object({
+    cursor: z.string().nullable(),
+    hasMore: z.boolean(),
+    total: z.number().optional(),
+  }),
+});
+
+export const SpendingByMedicineSchema = z.object({
+  medicineId: z.string(),
+  medicineName: z.string(),
+  totalSpent: z.number(),
+  totalQuantity: z.number(),
+  avgUnitPrice: z.number(),
+  purchaseCount: z.number(),
+});
+
+export const SpendingByPeriodSchema = z.object({
+  period: z.string(),
+  totalSpent: z.number(),
+});
+
+export const SpendingSummaryResponseSchema = z.object({
+  totalSpent: z.number(),
+  currency: z.string().nullable(),
+  byMedicine: z.array(SpendingByMedicineSchema),
+  byPeriod: z.array(SpendingByPeriodSchema),
+});
+
+// Type exports
+export type CabinetEventQueryInput = z.infer<typeof CabinetEventQuerySchema>;
+export type SpendingSummaryQueryInput = z.infer<typeof SpendingSummaryQuerySchema>;
+export type DiscardCabinetItemInput = z.infer<typeof DiscardCabinetItemSchema>;
diff --git a/packages/shared/src/validation/cabinet.schemas.ts b/packages/shared/src/validation/cabinet.schemas.ts
index 2d77822..10de342 100644
--- a/packages/shared/src/validation/cabinet.schemas.ts
+++ b/packages/shared/src/validation/cabinet.schemas.ts
@@ -10,6 +10,12 @@ export const CreateCabinetItemSchema = z.object({
   quantity: z.number().nonnegative(),
   unit: z.nativeEnum(DosageUnit),
   expirationDate: z.iso.datetime().optional(),
+  purchaseDate: z.iso.datetime().optional(),
+  unitPrice: z.number().nonnegative().optional(),
+  totalPrice: z.number().nonnegative().optional(),
+  currency: z.string().max(10).trim().optional(),
+  storeId: z.string().min(1).optional(),
+  storeName: z.string().max(200).trim().optional(),
   notes: z.string().max(1000).trim().optional(),
 });
 
@@ -50,6 +56,12 @@ export const CabinetItemResponseSchema = z.object({
   unit: z.string(),
   expirationDate: z.string().optional(),
   status: z.string(),
+  purchaseDate: z.string().optional(),
+  unitPrice: z.number().optional(),
+  totalPrice: z.number().optional(),
+  currency: z.string().optional(),
+  storeId: z.string().optional(),
+  storeName: z.string().optional(),
   notes: z.string().optional(),
   createdBy: z.string(),
   createdAt: z.string(),
diff --git a/packages/shared/src/validation/index.ts b/packages/shared/src/validation/index.ts
index cd8bdc4..f588e55 100644
--- a/packages/shared/src/validation/index.ts
+++ b/packages/shared/src/validation/index.ts
@@ -2,3 +2,6 @@ export * from './user.schemas.js';
 export * from './household.schemas.js';
 export * from './medicine.schemas.js';
 export * from './cabinet.schemas.js';
+export * from './cabinet-event.schemas.js';
+export * from './regimen.schemas.js';
+export * from './organizer.schemas.js';
diff --git a/packages/shared/src/validation/organizer.schemas.test.ts b/packages/shared/src/validation/organizer.schemas.test.ts
new file mode 100644
index 0000000..e6cf8ac
--- /dev/null
+++ b/packages/shared/src/validation/organizer.schemas.test.ts
@@ -0,0 +1,113 @@
+import { describe, it, expect } from 'vitest';
+import { OrganizerFillStatus } from '../enums/regimen.enums.js';
+import {
+  OrganizerPreviewSchema,
+  OrganizerFillSchema,
+  OrganizerFillQuerySchema,
+} from './organizer.schemas.js';
+
+describe('OrganizerPreviewSchema', () => {
+  it('accepts valid input', () => {
+    const result = OrganizerPreviewSchema.safeParse({
+      regimenId: 'reg-1',
+      numberOfDays: 7,
+    });
+    expect(result.success).toBe(true);
+  });
+
+  it('defaults numberOfDays to 7', () => {
+    const result = OrganizerPreviewSchema.safeParse({ regimenId: 'reg-1' });
+    expect(result.success).toBe(true);
+    if (result.success) {
+      expect(result.data.numberOfDays).toBe(7);
+    }
+  });
+
+  it('rejects missing regimenId', () => {
+    const result = OrganizerPreviewSchema.safeParse({ numberOfDays: 7 });
+    expect(result.success).toBe(false);
+  });
+
+  it('rejects numberOfDays over 90', () => {
+    const result = OrganizerPreviewSchema.safeParse({
+      regimenId: 'reg-1',
+      numberOfDays: 91,
+    });
+    expect(result.success).toBe(false);
+  });
+
+  it('rejects numberOfDays of 0', () => {
+    const result = OrganizerPreviewSchema.safeParse({
+      regimenId: 'reg-1',
+      numberOfDays: 0,
+    });
+    expect(result.success).toBe(false);
+  });
+});
+
+describe('OrganizerFillSchema', () => {
+  it('accepts valid input', () => {
+    const result = OrganizerFillSchema.safeParse({
+      regimenId: 'reg-1',
+      numberOfDays: 7,
+      allowPartial: true,
+    });
+    expect(result.success).toBe(true);
+  });
+
+  it('defaults allowPartial to false', () => {
+    const result = OrganizerFillSchema.safeParse({ regimenId: 'reg-1' });
+    expect(result.success).toBe(true);
+    if (result.success) {
+      expect(result.data.allowPartial).toBe(false);
+    }
+  });
+
+  it('accepts optional notes', () => {
+    const result = OrganizerFillSchema.safeParse({
+      regimenId: 'reg-1',
+      notes: 'Weekly fill',
+    });
+    expect(result.success).toBe(true);
+  });
+
+  it('rejects notes over 1000 chars', () => {
+    const result = OrganizerFillSchema.safeParse({
+      regimenId: 'reg-1',
+      notes: 'x'.repeat(1001),
+    });
+    expect(result.success).toBe(false);
+  });
+});
+
+describe('OrganizerFillQuerySchema', () => {
+  it('applies default limit', () => {
+    const result = OrganizerFillQuerySchema.safeParse({});
+    expect(result.success).toBe(true);
+    if (result.success) {
+      expect(result.data.limit).toBe(20);
+    }
+  });
+
+  it('accepts status filter', () => {
+    const result = OrganizerFillQuerySchema.safeParse({
+      status: OrganizerFillStatus.COMPLETED,
+    });
+    expect(result.success).toBe(true);
+  });
+
+  it('accepts regimenId filter', () => {
+    const result = OrganizerFillQuerySchema.safeParse({ regimenId: 'reg-1' });
+    expect(result.success).toBe(true);
+  });
+
+  it('rejects invalid status', () => {
+    const result = OrganizerFillQuerySchema.safeParse({ status: 'invalid' });
+    expect(result.success).toBe(false);
+  });
+
+  it('rejects limit over 100', () => {
+    const result = OrganizerFillQuerySchema.safeParse({ limit: 101 });
+    expect(result.success).toBe(false);
+  });
+});
diff --git a/packages/shared/src/validation/organizer.schemas.ts b/packages/shared/src/validation/organizer.schemas.ts
new file mode 100644
index 0000000..7e2796f
--- /dev/null
+++ b/packages/shared/src/validation/organizer.schemas.ts
@@ -0,0 +1,93 @@
+import { z } from 'zod/v4';
+import { OrganizerFillStatus } from '../enums/regimen.enums.js';
+
+// --- Request ---
+
+export const OrganizerPreviewSchema = z.object({
+  regimenId: z.string().min(1),
+  numberOfDays: z.number().int().min(1).max(90).default(7),
+});
+
+export const OrganizerFillSchema = z.object({
+  regimenId: z.string().min(1),
+  numberOfDays: z.number().int().min(1).max(90).default(7),
+  allowPartial: z.boolean().default(false),
+  notes: z.string().max(1000).trim().optional(),
+});
+
+export const OrganizerFillQuerySchema = z.object({
+  regimenId: z.string().optional(),
+  status: z.nativeEnum(OrganizerFillStatus).optional(),
+  cursor: z.string().optional(),
+  limit: z.coerce.number().int().min(1).max(100).default(20),
+});
+
+// --- Response ---
+
+export const OrganizerDeductionResponseSchema = z.object({
+  cabinetItemId: z.string(),
+  quantityTaken: z.number(),
+});
+
+export const OrganizerPreviewItemSchema = z.object({
+  medicineId: z.string(),
+  medicineName: z.string(),
+  quantityNeeded: z.number(),
+  quantityAvailable: z.number(),
+  isShort: z.boolean(),
+  shortage: z.number(),
+  cabinetBreakdown: z.array(
+    z.object({
+      cabinetItemId: z.string(),
+      expirationDate: z.string().nullable(),
+      quantityToTake: z.number(),
+    }),
+  ),
+});
+
+export const OrganizerPreviewResponseSchema = z.object({
+  regimenName: z.string(),
+  numberOfDays: z.number(),
+  items: z.array(OrganizerPreviewItemSchema),
+  canFillCompletely: z.boolean(),
+  hasShortages: z.boolean(),
+});
+
+export const OrganizerFillItemResponseSchema = z.object({
+  medicineId: z.string(),
+  medicineName: z.string(),
+  quantityNeeded: z.number(),
+  quantityTaken: z.number(),
+  wasShort: z.boolean(),
+  shortage: z.number(),
+  deductions: z.array(OrganizerDeductionResponseSchema),
+});
+
+export const OrganizerFillResponseSchema = z.object({
+  _id: z.string(),
+  householdId: z.string(),
+  userId: z.string(),
+  regimenId: z.string(),
+  regimenName: z.string(),
+  numberOfDays: z.number(),
+  fillDate: z.string(),
+  items: z.array(OrganizerFillItemResponseSchema),
+  status: z.string(),
+  notes: z.string().optional(),
+  createdAt: z.string(),
+  updatedAt: z.string(),
+});
+
+export const OrganizerFillListResponseSchema = z.object({
+  data: z.array(OrganizerFillResponseSchema),
+  pagination: z.object({
+    cursor: z.string().nullable(),
+    hasMore: z.boolean(),
+    total: z.number().optional(),
+  }),
+});
+
+// Type exports
+export type OrganizerPreviewInput = z.infer<typeof OrganizerPreviewSchema>;
+export type OrganizerFillInput = z.infer<typeof OrganizerFillSchema>;
+export type OrganizerFillQueryInput = z.infer<typeof OrganizerFillQuerySchema>;
diff --git a/packages/shared/src/validation/regimen.schemas.test.ts b/packages/shared/src/validation/regimen.schemas.test.ts
new file mode 100644
index 0000000..bec0e87
--- /dev/null
+++ b/packages/shared/src/validation/regimen.schemas.test.ts
@@ -0,0 +1,157 @@
+import { describe, it, expect } from 'vitest';
+import { DosageUnit } from '../enums/medicine.enums.js';
+import { DosageFrequency, TimeOfDay } from '../enums/regimen.enums.js';
+import {
+  CreateRegimenSchema,
+  UpdateRegimenSchema,
+  RegimenQuerySchema,
+  RegimenMedicationInputSchema,
+} from './regimen.schemas.js';
+
+const validMedication = {
+  medicineId: 'med-1',
+  dosage: 1,
+  dosageUnit: DosageUnit.TABLET,
+  frequency: DosageFrequency.DAILY,
+};
+
+describe('RegimenMedicationInputSchema', () => {
+  it('accepts valid medication', () => {
+    const result = RegimenMedicationInputSchema.safeParse(validMedication);
+    expect(result.success).toBe(true);
+  });
+
+  it('accepts full medication with optional fields', () => {
+    const result = RegimenMedicationInputSchema.safeParse({
+      ...validMedication,
+      timeOfDay: TimeOfDay.MORNING,
+      instructions: 'Take with food',
+    });
+    expect(result.success).toBe(true);
+  });
+
+  it('accepts custom frequency with customFrequencyPerDay', () => {
+    const result = RegimenMedicationInputSchema.safeParse({
+      ...validMedication,
+      frequency: DosageFrequency.CUSTOM,
+      customFrequencyPerDay: 4,
+    });
+    expect(result.success).toBe(true);
+  });
+
+  it('rejects custom frequency without customFrequencyPerDay', () => {
+    const result = RegimenMedicationInputSchema.safeParse({
+      ...validMedication,
+      frequency: DosageFrequency.CUSTOM,
+    });
+    expect(result.success).toBe(false);
+  });
+
+  it('rejects zero dosage', () => {
+    const result = RegimenMedicationInputSchema.safeParse({
+      ...validMedication,
+      dosage: 0,
+    });
+    expect(result.success).toBe(false);
+  });
+
+  it('rejects missing medicineId', () => {
+    const { medicineId: _, ...rest } = validMedication;
+    const result = RegimenMedicationInputSchema.safeParse(rest);
+    expect(result.success).toBe(false);
+  });
+});
+
+describe('CreateRegimenSchema', () => {
+  const validRegimen = {
+    name: 'Daily medications',
+    medications: [validMedication],
+  };
+
+  it('accepts valid input', () => {
+    const result = CreateRegimenSchema.safeParse(validRegimen);
+    expect(result.success).toBe(true);
+  });
+
+  it('defaults isActive to true', () => {
+    const result = CreateRegimenSchema.safeParse(validRegimen);
+    expect(result.success).toBe(true);
+    if (result.success) {
+      expect(result.data.isActive).toBe(true);
+    }
+  });
+
+  it('accepts isActive override', () => {
+    const result = CreateRegimenSchema.safeParse({ ...validRegimen, isActive: false });
+    expect(result.success).toBe(true);
+    if (result.success) {
+      expect(result.data.isActive).toBe(false);
+    }
+  });
+
+  it('rejects empty name', () => {
+    const result = CreateRegimenSchema.safeParse({ ...validRegimen, name: '' });
+    expect(result.success).toBe(false);
+  });
+
+  it('rejects empty medications array', () => {
+    const result = CreateRegimenSchema.safeParse({ ...validRegimen, medications: [] });
+    expect(result.success).toBe(false);
+  });
+
+  it('accepts multiple medications', () => {
+    const result = CreateRegimenSchema.safeParse({
+      ...validRegimen,
+      medications: [
+        validMedication,
+        { ...validMedication, medicineId: 'med-2', dosage: 2 },
+      ],
+    });
+    expect(result.success).toBe(true);
+  });
+});
+
+describe('UpdateRegimenSchema', () => {
+  it('accepts partial update', () => {
+    const result = UpdateRegimenSchema.safeParse({ name: 'Updated name' });
+    expect(result.success).toBe(true);
+  });
+
+  it('accepts empty object', () => {
+    const result = UpdateRegimenSchema.safeParse({});
+    expect(result.success).toBe(true);
+  });
+
+  it('accepts isActive toggle', () => {
+    const result = UpdateRegimenSchema.safeParse({ isActive: false });
+    expect(result.success).toBe(true);
+  });
+
+  it('rejects empty medications array when provided', () => {
+    const result = UpdateRegimenSchema.safeParse({ medications: [] });
+    expect(result.success).toBe(false);
+  });
+});
+
+describe('RegimenQuerySchema', () => {
+  it('applies default limit', () => {
+    const result = RegimenQuerySchema.safeParse({});
+    expect(result.success).toBe(true);
+    if (result.success) {
+      expect(result.data.limit).toBe(20);
+    }
+  });
+
+  it('parses isActive string to boolean', () => {
+    const result = RegimenQuerySchema.safeParse({ isActive: 'true' });
+    expect(result.success).toBe(true);
+    if (result.success) {
+      expect(result.data.isActive).toBe(true);
+    }
+  });
+
+  it('rejects limit over 100', () => {
+    const result = RegimenQuerySchema.safeParse({ limit: 101 });
+    expect(result.success).toBe(false);
+  });
+});
diff --git a/packages/shared/src/validation/regimen.schemas.ts b/packages/shared/src/validation/regimen.schemas.ts
new file mode 100644
index 0000000..7755d3e
--- /dev/null
+++ b/packages/shared/src/validation/regimen.schemas.ts
@@ -0,0 +1,105 @@
+import { z } from 'zod/v4';
+import { DosageFrequency, TimeOfDay } from '../enums/regimen.enums.js';
+import { DosageUnit } from '../enums/medicine.enums.js';
+
+// --- RegimenMedication (embedded) ---
+
+export const RegimenMedicationInputSchema = z
+  .object({
+    medicineId: z.string().min(1),
+    dosage: z.number().positive(),
+    dosageUnit: z.nativeEnum(DosageUnit),
+    frequency: z.nativeEnum(DosageFrequency),
+    customFrequencyPerDay: z.number().int().positive().optional(),
+    timeOfDay: z.nativeEnum(TimeOfDay).optional(),
+    instructions: z.string().max(500).trim().optional(),
+  })
+  .refine(
+    (data) =>
+      data.frequency !== DosageFrequency.CUSTOM ||
+      data.customFrequencyPerDay !== undefined,
+    { message: 'customFrequencyPerDay is required when frequency is custom' },
+  );
+
+// --- Regimen ---
+
+export const CreateRegimenSchema = z.object({
+  name: z.string().min(1).max(200).trim(),
+  isActive: z.boolean().default(true),
+  medications: z.array(RegimenMedicationInputSchema).min(1),
+});
+
+export const UpdateRegimenSchema = z.object({
+  name: z.string().min(1).max(200).trim().optional(),
+  isActive: z.boolean().optional(),
+  medications: z.array(RegimenMedicationInputSchema).min(1).optional(),
+});
+
+export const RegimenQuerySchema = z.object({
+  isActive: z
+    .string()
+    .transform((v) => v === 'true')
+    .optional(),
+  cursor: z.string().optional(),
+  limit: z.coerce.number().int().min(1).max(100).default(20),
+});
+
+// --- Response ---
+
+export const RegimenMedicationResponseSchema = z.object({
+  medicineId: z.string(),
+  medicineName: z.string(),
+  medicineStrength: z.number(),
+  medicineStrengthUnit: z.string(),
+  medicineForm: z.string(),
+  dosage: z.number(),
+  dosageUnit: z.string(),
+  frequency: z.string(),
+  customFrequencyPerDay: z.number().optional(),
+  timeOfDay: z.string().optional(),
+  instructions: z.string().optional(),
+});
+
+export const RegimenResponseSchema = z.object({
+  _id: z.string(),
+  householdId: z.string(),
+  userId: z.string(),
+  name: z.string(),
+  isActive: z.boolean(),
+  medications: z.array(RegimenMedicationResponseSchema),
+  createdBy: z.string(),
+  createdAt: z.string(),
+  updatedAt: z.string(),
+});
+
+export const RegimenListResponseSchema = z.object({
+  data: z.array(RegimenResponseSchema),
+  pagination: z.object({
+    cursor: z.string().nullable(),
+    hasMore: z.boolean(),
+    total: z.number().optional(),
+  }),
+});
+
+export const BurnRateItemSchema = z.object({
+  medicineId: z.string(),
+  medicineName: z.string(),
+  dailyConsumption: z.number(),
+  totalInCabinet: z.number(),
+  daysUntilEmpty: z.number().nullable(),
+  earliestExpiry: z.string().nullable(),
+  avgUnitPrice: z.number().nullable(),
+  projectedDailyCost: z.number().nullable(),
+  projectedMonthlyCost: z.number().nullable(),
+  projectedYearlyCost: z.number().nullable(),
+  currency: z.string().nullable(),
+});
+
+export const BurnRateResponseSchema = z.object({
+  data: z.array(BurnRateItemSchema),
+});
+
+// Type exports
+export type CreateRegimenInput = z.infer<typeof CreateRegimenSchema>;
+export type UpdateRegimenInput = z.infer<typeof UpdateRegimenSchema>;
+export type RegimenQueryInput = z.infer<typeof RegimenQuerySchema>;
diff --git a/packages/web/src/app/(dashboard)/medicines/ActivityTab.tsx b/packages/web/src/app/(dashboard)/medicines/ActivityTab.tsx
new file mode 100644
index 0000000..31c2c6c
--- /dev/null
+++ b/packages/web/src/app/(dashboard)/medicines/ActivityTab.tsx
@@ -0,0 +1,420 @@
+'use client';
+
+import { useState, useEffect, useCallback } from 'react';
+import { listCabinetEvents, getSpendingSummary } from '@/services/cabinet-events';
+import { listMedicines } from '@/services/medicines';
+import { CabinetEventType } from '@meshitrack/shared';
+import type { z } from 'zod/v4';
+import type {
+  CabinetEventResponseSchema,
+  SpendingSummaryResponseSchema,
+} from '@meshitrack/shared';
+
+type CabinetEvent = z.infer<typeof CabinetEventResponseSchema>;
+type SpendingSummary = z.infer<typeof SpendingSummaryResponseSchema>;
+
+type MedicineOption = {
+  _id: string;
+  name: string;
+};
+
+const EVENT_TYPE_LABELS: Record<string, string> = {
+  purchased: 'Purchased',
+  consumed: 'Consumed',
+  adjusted: 'Adjusted',
+  discarded: 'Discarded',
+  restored: 'Restored',
+  deleted: 'Deleted',
+};
+
+const EVENT_TYPE_COLORS: Record<string, string> = {
+  purchased: 'bg-green-100 text-green-700',
+  consumed: 'bg-blue-100 text-blue-700',
+  adjusted: 'bg-yellow-100 text-yellow-700',
+  discarded: 'bg-red-100 text-red-700',
+  restored: 'bg-purple-100 text-purple-700',
+  deleted: 'bg-gray-100 text-gray-600',
+};
+
+function formatDateTime(dateStr: string): string {
+  return new Date(dateStr).toLocaleString();
+}
+
+function formatQuantityChange(event: CabinetEvent): string {
+  const sign = event.quantity > 0 ? '+' : '';
+  return `${sign}${event.quantity}`;
+}
+
+function QuantityBadge({ quantity }: { quantity: number }) {
+  const isPositive = quantity > 0;
+  return (
+    <span
+      className={`text-sm font-semibold ${isPositive ? 'text-green-600' : 'text-red-600'}`}
+    >
+      {isPositive ? '+' : ''}
+      {quantity}
+    </span>
+  );
+}
+
+// --- Spending summary ---
+
+function SpendingSummaryView({
+  householdId,
+  medicines,
+}: {
+  householdId: string;
+  medicines: MedicineOption[];
+}) {
+  const [summary, setSummary] = useState<SpendingSummary | null>(null);
+  const [loading, setLoading] = useState(true);
+  const [period, setPeriod] = useState<'month' | 'quarter' | 'year'>('month');
+  const [medicineId, setMedicineId] = useState('');
+  const [error, setError] = useState('');
+
+  const fetchSummary = useCallback(async () => {
+    setLoading(true);
+    setError('');
+    try {
+      const result = await getSpendingSummary(householdId, {
+        period,
+        medicineId: medicineId || undefined,
+      });
+      setSummary(result);
+    } catch (err) {
+      setError(err instanceof Error ? err.message : 'Failed to load spending summary');
+    } finally {
+      setLoading(false);
+    }
+  }, [householdId, period, medicineId]);
+
+  useEffect(() => {
+    fetchSummary();
+  }, [fetchSummary]);
+
+  const PERIOD_LABELS = { month: 'This month', quarter: 'This quarter', year: 'This year' };
+
+  return (
+    <div className="rounded-xl border bg-white p-6 shadow-sm">
+      <div className="flex items-center justify-between mb-4 flex-wrap gap-3">
+        <h2 className="text-lg font-semibold">Spending Summary</h2>
+        <div className="flex items-center gap-2">
+          <select
+            value={period}
+            onChange={(e) => setPeriod(e.target.value as 'month' | 'quarter' | 'year')}
+            className="rounded-lg border px-3 py-2 text-sm focus:border-primary-500 focus:ring-1 focus:ring-primary-500 focus:outline-none"
+          >
+            {Object.entries(PERIOD_LABELS).map(([v, label]) => (
+              <option key={v} value={v}>
+                {label}
+              </option>
+            ))}
+          </select>
+          <select
+            value={medicineId}
+            onChange={(e) => setMedicineId(e.target.value)}
+            className="rounded-lg border px-3 py-2 text-sm focus:border-primary-500 focus:ring-1 focus:ring-primary-500 focus:outline-none"
+          >
+            <option value="">All medicines</option>
+            {medicines.map((m) => (
+              <option key={m._id} value={m._id}>
+                {m.name}
+              </option>
+            ))}
+          </select>
+        </div>
+      </div>
+
+      {error && (
+        <div className="mb-4 rounded-lg bg-red-50 border border-red-200 p-3 text-sm text-red-700">
+          {error}
+        </div>
+      )}
+
+      {loading ? (
+        <div className="animate-pulse space-y-2">
+          <div className="h-6 w-32 rounded bg-gray-200" />
+          <div className="h-20 rounded bg-gray-200" />
+        </div>
+      ) : summary && summary.totalSpent > 0 ? (
+        <div className="space-y-5">
+          <div className="text-2xl font-bold text-gray-900">
+            {summary.currency ? `${summary.currency} ` : ''}
+            {summary.totalSpent.toFixed(2)}
+            <span className="text-sm font-normal text-gray-500 ml-2">total spent</span>
+          </div>
+
+          {summary.byMedicine.length > 0 && (
+            <div>
+              <h3 className="text-sm font-semibold text-gray-700 mb-2">By medicine</h3>
+              <div className="space-y-2">
+                {summary.byMedicine.map((item) => (
+                  <div
+                    key={item.medicineId}
+                    className="flex items-center justify-between rounded-lg border p-3"
+                  >
+                    <div>
+                      <span className="text-sm font-medium text-gray-900">
+                        {item.medicineName}
+                      </span>
+                      <span className="ml-2 text-xs text-gray-500">
+                        {item.purchaseCount} purchase{item.purchaseCount !== 1 ? 's' : ''} &bull;{' '}
+                        avg {summary.currency ? `${summary.currency} ` : ''}
+                        {item.avgUnitPrice.toFixed(2)}/unit
+                      </span>
+                    </div>
+                    <span className="text-sm font-semibold text-gray-800">
+                      {summary.currency ? `${summary.currency} ` : ''}
+                      {item.totalSpent.toFixed(2)}
+                    </span>
+                  </div>
+                ))}
+              </div>
+            </div>
+          )}
+
+          {summary.byPeriod.length > 0 && (
+            <div>
+              <h3 className="text-sm font-semibold text-gray-700 mb-2">By period</h3>
+              <div className="space-y-2">
+                {summary.byPeriod.map((item) => (
+                  <div
+                    key={item.period}
+                    className="flex items-center justify-between rounded-lg border p-3"
+                  >
+                    <span className="text-sm text-gray-700">{item.period}</span>
+                    <span className="text-sm font-semibold text-gray-800">
+                      {summary.currency ? `${summary.currency} ` : ''}
+                      {item.totalSpent.toFixed(2)}
+                    </span>
+                  </div>
+                ))}
+              </div>
+            </div>
+          )}
+        </div>
+      ) : (
+        <p className="text-sm text-gray-500 py-4 text-center">
+          No purchase data found for this period.
+        </p>
+      )}
+    </div>
+  );
+}
+
+// --- Event timeline ---
+
+function EventTimeline({
+  householdId,
+  medicines,
+}: {
+  householdId: string;
+  medicines: MedicineOption[];
+}) {
+  const [events, setEvents] = useState<CabinetEvent[]>([]);
+  const [loading, setLoading] = useState(true);
+  const [error, setError] = useState('');
+  const [filterEventType, setFilterEventType] = useState('');
+  const [filterMedicineId, setFilterMedicineId] = useState('');
+  const [startDate, setStartDate] = useState('');
+  const [endDate, setEndDate] = useState('');
+  const [cursor, setCursor] = useState<string | null>(null);
+  const [hasMore, setHasMore] = useState(false);
+
+  const fetchEvents = useCallback(
+    async (append = false) => {
+      if (!append) setLoading(true);
+      setError('');
+      try {
+        const result = await listCabinetEvents(householdId, {
+          eventType: filterEventType || undefined,
+          medicineId: filterMedicineId || undefined,
+          startDate: startDate ? new Date(startDate).toISOString() : undefined,
+          endDate: endDate ? new Date(endDate).toISOString() : undefined,
+          cursor: append ? (cursor ?? undefined) : undefined,
+          limit: 20,
+        });
+        setEvents((prev) => (append ? [...prev, ...result.data] : result.data));
+        setCursor(result.pagination.cursor);
+        setHasMore(result.pagination.hasMore);
+      } catch (err) {
+        setError(err instanceof Error ? err.message : 'Failed to load events');
+      } finally {
+        setLoading(false);
+      }
+    },
+    [householdId, filterEventType, filterMedicineId, startDate, endDate, cursor],
+  );
+
+  // Refetch from scratch when filters change
+  useEffect(() => {
+    setCursor(null);
+    setEvents([]);
+    fetchEvents(false);
+    // eslint-disable-next-line react-hooks/exhaustive-deps
+  }, [householdId, filterEventType, filterMedicineId, startDate, endDate]);
+
+  return (
+    <div className="rounded-xl border bg-white p-6 shadow-sm">
+      <h2 className="text-lg font-semibold mb-4">Cabinet Activity</h2>
+
+      <div className="mb-4 flex flex-wrap items-center gap-3">
+        <select
+          value={filterEventType}
+          onChange={(e) => setFilterEventType(e.target.value)}
+          className="rounded-lg border px-3 py-2 text-sm focus:border-primary-500 focus:ring-1 focus:ring-primary-500 focus:outline-none"
+        >
+          <option value="">All event types</option>
+          {Object.values(CabinetEventType).map((t) => (
+            <option key={t} value={t}>
+              {EVENT_TYPE_LABELS[t] ?? t}
+            </option>
+          ))}
+        </select>
+        <select
+          value={filterMedicineId}
+          onChange={(e) => setFilterMedicineId(e.target.value)}
+          className="rounded-lg border px-3 py-2 text-sm focus:border-primary-500 focus:ring-1 focus:ring-primary-500 focus:outline-none"
+        >
+          <option value="">All medicines</option>
+          {medicines.map((m) => (
+            <option key={m._id} value={m._id}>
+              {m.name}
+            </option>
+          ))}
+        </select>
+        <input
+          type="date"
+          value={startDate}
+          onChange={(e) => setStartDate(e.target.value)}
+          className="rounded-lg border px-3 py-2 text-sm focus:border-primary-500 focus:ring-1 focus:ring-primary-500 focus:outline-none"
+          title="Start date"
+        />
+        <input
+          type="date"
+          value={endDate}
+          onChange={(e) => setEndDate(e.target.value)}
+          className="rounded-lg border px-3 py-2 text-sm focus:border-primary-500 focus:ring-1 focus:ring-primary-500 focus:outline-none"
+          title="End date"
+        />
+        {(filterEventType || filterMedicineId || startDate || endDate) && (
+          <button
+            onClick={() => {
+              setFilterEventType('');
+              setFilterMedicineId('');
+              setStartDate('');
+              setEndDate('');
+            }}
+            className="text-sm text-gray-500 underline"
+          >
+            Clear filters
+          </button>
+        )}
+      </div>
+
+      {error && (
+        <div className="mb-4 rounded-lg bg-red-50 border border-red-200 p-3 text-sm text-red-700">
+          {error}
+          <button onClick={() => setError('')} className="ml-2 underline">
+            Dismiss
+          </button>
+        </div>
+      )}
+
+      {loading ? (
+        <div className="space-y-3">
+          {Array.from({ length: 5 }).map((_, i) => (
+            <div key={i} className="animate-pulse h-14 rounded-lg bg-gray-200" />
+          ))}
+        </div>
+      ) : events.length === 0 ? (
+        <p className="text-sm text-center text-gray-500 py-6">
+          No events found for the selected filters.
+        </p>
+      ) : (
+        <div className="relative">
+          {/* Timeline line */}
+          <div className="absolute left-4 top-0 bottom-0 w-px bg-gray-200" />
+          <div className="space-y-4 pl-10">
+            {events.map((event) => (
+              <div key={event._id} className="relative">
+                {/* Dot */}
+                <div
+                  className={`absolute -left-6 top-2 h-3 w-3 rounded-full border-2 border-white ${
+                    event.quantity > 0 ? 'bg-green-400' : 'bg-red-400'
+                  }`}
+                />
+                <div className="rounded-lg border bg-gray-50 p-3">
+                  <div className="flex items-start justify-between gap-3 flex-wrap">
+                    <div className="flex items-center gap-2 flex-wrap">
+                      <span
+                        className={`rounded-full px-2 py-0.5 text-xs font-medium ${EVENT_TYPE_COLORS[event.eventType] ?? 'bg-gray-100 text-gray-600'}`}
+                      >
+                        {EVENT_TYPE_LABELS[event.eventType] ?? event.eventType}
+                      </span>
+                      <span className="text-sm font-medium text-gray-900">
+                        {event.medicineName}
+                      </span>
+                      <QuantityBadge quantity={event.quantity} />
+                      <span className="text-xs text-gray-500">
+                        {event.quantityBefore} &rarr; {event.quantityAfter}
+                      </span>
+                    </div>
+                    <span className="text-xs text-gray-400 shrink-0">
+                      {formatDateTime(event.createdAt)}
+                    </span>
+                  </div>
+                  {(event.reason || event.notes || event.storeName || event.totalPrice) && (
+                    <div className="mt-1 flex flex-wrap gap-3 text-xs text-gray-500">
+                      {event.reason && <span>Reason: {event.reason}</span>}
+                      {event.storeName && <span>Store: {event.storeName}</span>}
+                      {event.totalPrice && (
+                        <span>
+                          {event.currency ? `${event.currency} ` : ''}
+                          {event.totalPrice.toFixed(2)}
+                        </span>
+                      )}
+                      {event.notes && <span>{event.notes}</span>}
+                    </div>
+                  )}
+                </div>
+              </div>
+            ))}
+          </div>
+
+          {hasMore && (
+            <div className="mt-4 text-center">
+              <button
+                onClick={() => fetchEvents(true)}
+                className="rounded-lg border px-4 py-2 text-sm font-medium hover:bg-gray-50 transition-colors"
+              >
+                Load more
+              </button>
+            </div>
+          )}
+        </div>
+      )}
+    </div>
+  );
+}
+
+// --- Main component ---
+
+export function ActivityTab({ householdId }: { householdId: string }) {
+  const [medicines, setMedicines] = useState<MedicineOption[]>([]);
+
+  useEffect(() => {
+    listMedicines(householdId, { limit: 100 })
+      .then((r) =>
+        setMedicines(r.data.map((m: { _id: string; name: string }) => ({ _id: m._id, name: m.name }))),
+      )
+      .catch(() => {});
+  }, [householdId]);
+
+  return (
+    <div className="space-y-6">
+      <SpendingSummaryView householdId={householdId} medicines={medicines} />
+      <EventTimeline householdId={householdId} medicines={medicines} />
+    </div>
+  );
+}
diff --git a/packages/web/src/app/(dashboard)/medicines/OrganizerTab.tsx b/packages/web/src/app/(dashboard)/medicines/OrganizerTab.tsx
new file mode 100644
index 0000000..211cd65
--- /dev/null
+++ b/packages/web/src/app/(dashboard)/medicines/OrganizerTab.tsx
@@ -0,0 +1,455 @@
+'use client';
+
+import { useState, useEffect, useCallback } from 'react';
+import {
+  listFills,
+  previewFill,
+  executeFill,
+  undoFill,
+} from '@/services/organizer';
+import { listRegimens } from '@/services/regimens';
+import { OrganizerFillStatus } from '@meshitrack/shared';
+import type { z } from 'zod/v4';
+import type {
+  OrganizerFillResponseSchema,
+  OrganizerPreviewResponseSchema,
+  RegimenResponseSchema,
+} from '@meshitrack/shared';
+
+type OrganizerFill = z.infer<typeof OrganizerFillResponseSchema>;
+type OrganizerPreview = z.infer<typeof OrganizerPreviewResponseSchema>;
+type Regimen = z.infer<typeof RegimenResponseSchema>;
+
+const STATUS_LABELS: Record<string, string> = {
+  completed: 'Completed',
+  partial: 'Partial',
+  reversed: 'Reversed',
+};
+
+const STATUS_COLORS: Record<string, string> = {
+  completed: 'bg-green-100 text-green-700',
+  partial: 'bg-yellow-100 text-yellow-700',
+  reversed: 'bg-gray-100 text-gray-500',
+};
+
+function formatDate(dateStr: string): string {
+  return new Date(dateStr).toLocaleDateString();
+}
+
+// --- Preview result display ---
+
+function PreviewResult({
+  preview,
+  onConfirm,
+  onCancel,
+  submitting,
+  allowPartial,
+  onTogglePartial,
+}: {
+  preview: OrganizerPreview;
+  onConfirm: () => void;
+  onCancel: () => void;
+  submitting: boolean;
+  allowPartial: boolean;
+  onTogglePartial: (v: boolean) => void;
+}) {
+  return (
+    <div className="rounded-xl border bg-white p-6 shadow-sm space-y-5">
+      <div className="flex items-center justify-between">
+        <h3 className="text-base font-semibold">
+          Preview: {preview.regimenName} &mdash; {preview.numberOfDays} day
+          {preview.numberOfDays !== 1 ? 's' : ''}
+        </h3>
+        {preview.hasShortages ? (
+          <span className="rounded-full bg-yellow-100 px-3 py-1 text-xs font-medium text-yellow-700">
+            Shortages detected
+          </span>
+        ) : (
+          <span className="rounded-full bg-green-100 px-3 py-1 text-xs font-medium text-green-700">
+            Ready to fill
+          </span>
+        )}
+      </div>
+
+      <div className="space-y-2">
+        {preview.items.map((item) => (
+          <div
+            key={item.medicineId}
+            className={`rounded-lg border p-3 ${item.isShort ? 'border-yellow-300 bg-yellow-50' : 'border-gray-200'}`}
+          >
+            <div className="flex items-center justify-between">
+              <span className="text-sm font-medium text-gray-900">{item.medicineName}</span>
+              <div className="flex items-center gap-4 text-sm">
+                <span className="text-gray-500">
+                  Need: <strong>{item.quantityNeeded}</strong>
+                </span>
+                <span className="text-gray-500">
+                  Available: <strong>{item.quantityAvailable}</strong>
+                </span>
+                {item.isShort && (
+                  <span className="text-yellow-700 font-semibold">
+                    Short: {item.shortage}
+                  </span>
+                )}
+              </div>
+            </div>
+            {item.cabinetBreakdown.length > 0 && (
+              <div className="mt-2 flex flex-wrap gap-1">
+                {item.cabinetBreakdown.map((b, i) => (
+                  <span key={i} className="rounded bg-blue-50 px-2 py-0.5 text-xs text-blue-700">
+                    {b.quantityToTake} units
+                    {b.expirationDate ? ` (exp ${new Date(b.expirationDate).toLocaleDateString()})` : ''}
+                  </span>
+                ))}
+              </div>
+            )}
+          </div>
+        ))}
+      </div>
+
+      {preview.hasShortages && (
+        <div className="flex items-center gap-2">
+          <input
+            type="checkbox"
+            id="allowPartial"
+            checked={allowPartial}
+            onChange={(e) => onTogglePartial(e.target.checked)}
+            className="h-4 w-4 rounded border-gray-300 text-primary-600 focus:ring-primary-500"
+          />
+          <label htmlFor="allowPartial" className="text-sm text-gray-700">
+            Allow partial fill (fill what is available)
+          </label>
+        </div>
+      )}
+
+      <div className="flex gap-3">
+        <button
+          onClick={onConfirm}
+          disabled={submitting || (preview.hasShortages && !allowPartial)}
+          className="rounded-lg bg-primary-600 px-4 py-2 text-sm font-medium text-white hover:bg-primary-700 disabled:opacity-50 transition-colors"
+        >
+          {submitting ? 'Filling...' : 'Confirm fill'}
+        </button>
+        <button
+          onClick={onCancel}
+          className="rounded-lg border px-4 py-2 text-sm font-medium hover:bg-gray-50 transition-colors"
+        >
+          Back
+        </button>
+      </div>
+    </div>
+  );
+}
+
+// --- Fill wizard ---
+
+function FillWizard({
+  householdId,
+  regimens,
+  onFilled,
+}: {
+  householdId: string;
+  regimens: Regimen[];
+  onFilled: () => void;
+}) {
+  const [regimenId, setRegimenId] = useState('');
+  const [numberOfDays, setNumberOfDays] = useState(7);
+  const [notes, setNotes] = useState('');
+  const [allowPartial, setAllowPartial] = useState(false);
+  const [preview, setPreview] = useState<OrganizerPreview | null>(null);
+  const [previewing, setPreviewing] = useState(false);
+  const [filling, setFilling] = useState(false);
+  const [error, setError] = useState('');
+
+  const activeRegimens = regimens.filter((r) => r.isActive);
+
+  async function handlePreview(e: React.FormEvent) {
+    e.preventDefault();
+    setError('');
+    setPreviewing(true);
+    try {
+      const result = await previewFill(householdId, { regimenId, numberOfDays });
+      setPreview(result);
+      setAllowPartial(false);
+    } catch (err) {
+      setError(err instanceof Error ? err.message : 'Failed to generate preview');
+    } finally {
+      setPreviewing(false);
+    }
+  }
+
+  async function handleFill() {
+    setError('');
+    setFilling(true);
+    try {
+      await executeFill(householdId, { regimenId, numberOfDays, allowPartial, notes: notes || undefined });
+      setPreview(null);
+      setRegimenId('');
+      setNumberOfDays(7);
+      setNotes('');
+      setAllowPartial(false);
+      onFilled();
+    } catch (err) {
+      setError(err instanceof Error ? err.message : 'Fill failed');
+      setPreview(null);
+    } finally {
+      setFilling(false);
+    }
+  }
+
+  if (preview) {
+    return (
+      <>
+        {error && (
+          <div className="mb-4 rounded-lg bg-red-50 border border-red-200 p-3 text-sm text-red-700">
+            {error}
+          </div>
+        )}
+        <PreviewResult
+          preview={preview}
+          onConfirm={handleFill}
+          onCancel={() => setPreview(null)}
+          submitting={filling}
+          allowPartial={allowPartial}
+          onTogglePartial={setAllowPartial}
+        />
+      </>
+    );
+  }
+
+  return (
+    <div className="rounded-xl border bg-white p-6 shadow-sm">
+      <h2 className="text-lg font-semibold mb-4">Fill Pill Organizer</h2>
+      {error && (
+        <div className="mb-4 rounded-lg bg-red-50 border border-red-200 p-3 text-sm text-red-700">
+          {error}
+        </div>
+      )}
+      {activeRegimens.length === 0 ? (
+        <p className="text-sm text-gray-500">
+          No active regimens found. Create and activate a regimen before filling.
+        </p>
+      ) : (
+        <form onSubmit={handlePreview} className="space-y-4">
+          <div className="grid grid-cols-1 gap-4 md:grid-cols-2">
+            <div>
+              <label className="block text-sm font-medium text-gray-700 mb-1">Regimen</label>
+              <select
+                required
+                value={regimenId}
+                onChange={(e) => setRegimenId(e.target.value)}
+                className="w-full rounded-lg border px-3 py-2 text-sm focus:border-primary-500 focus:ring-1 focus:ring-primary-500 focus:outline-none"
+              >
+                <option value="">Select regimen...</option>
+                {activeRegimens.map((r) => (
+                  <option key={r._id} value={r._id}>
+                    {r.name} ({r.medications.length} medication{r.medications.length !== 1 ? 's' : ''})
+                  </option>
+                ))}
+              </select>
+            </div>
+            <div>
+              <label className="block text-sm font-medium text-gray-700 mb-1">Number of days</label>
+              <input
+                type="number"
+                required
+                min={1}
+                max={90}
+                value={numberOfDays}
+                onChange={(e) => setNumberOfDays(Number(e.target.value))}
+                className="w-full rounded-lg border px-3 py-2 text-sm focus:border-primary-500 focus:ring-1 focus:ring-primary-500 focus:outline-none"
+              />
+            </div>
+            <div className="md:col-span-2">
+              <label className="block text-sm font-medium text-gray-700 mb-1">
+                Notes (optional)
+              </label>
+              <input
+                type="text"
+                maxLength={1000}
+                value={notes}
+                onChange={(e) => setNotes(e.target.value)}
+                placeholder="Any notes for this fill"
+                className="w-full rounded-lg border px-3 py-2 text-sm focus:border-primary-500 focus:ring-1 focus:ring-primary-500 focus:outline-none"
+              />
+            </div>
+          </div>
+          <button
+            type="submit"
+            disabled={previewing}
+            className="rounded-lg bg-primary-600 px-4 py-2 text-sm font-medium text-white hover:bg-primary-700 disabled:opacity-50 transition-colors"
+          >
+            {previewing ? 'Calculating...' : 'Preview fill'}
+          </button>
+        </form>
+      )}
+    </div>
+  );
+}
+
+// --- Fill history list ---
+
+function FillHistory({
+  householdId,
+  refreshKey,
+}: {
+  householdId: string;
+  refreshKey: number;
+}) {
+  const [fills, setFills] = useState<OrganizerFill[]>([]);
+  const [loading, setLoading] = useState(true);
+  const [error, setError] = useState('');
+  const [filterStatus, setFilterStatus] = useState('');
+
+  const fetchFills = useCallback(async () => {
+    setLoading(true);
+    try {
+      const result = await listFills(householdId, {
+        status: filterStatus || undefined,
+        limit: 50,
+      });
+      setFills(result.data);
+    } catch (err) {
+      setError(err instanceof Error ? err.message : 'Failed to load fill history');
+    } finally {
+      setLoading(false);
+    }
+  }, [householdId, filterStatus]);
+
+  useEffect(() => {
+    fetchFills();
+  }, [fetchFills, refreshKey]);
+
+  async function handleUndo(fillId: string) {
+    if (!confirm('Reverse this fill? Cabinet quantities will be restored.')) return;
+    try {
+      const updated = await undoFill(householdId, fillId);
+      setFills((prev) => prev.map((f) => (f._id === updated._id ? updated : f)));
+    } catch (err) {
+      setError(err instanceof Error ? err.message : 'Failed to undo fill');
+    }
+  }
+
+  return (
+    <div className="rounded-xl border bg-white p-6 shadow-sm">
+      <div className="flex items-center justify-between mb-4">
+        <h2 className="text-lg font-semibold">Fill History</h2>
+        <select
+          value={filterStatus}
+          onChange={(e) => setFilterStatus(e.target.value)}
+          className="rounded-lg border px-3 py-2 text-sm focus:border-primary-500 focus:ring-1 focus:ring-primary-500 focus:outline-none"
+        >
+          <option value="">All statuses</option>
+          {Object.values(OrganizerFillStatus).map((s) => (
+            <option key={s} value={s}>
+              {STATUS_LABELS[s] ?? s}
+            </option>
+          ))}
+        </select>
+      </div>
+
+      {error && (
+        <div className="mb-4 rounded-lg bg-red-50 border border-red-200 p-3 text-sm text-red-700">
+          {error}
+          <button onClick={() => setError('')} className="ml-2 underline">
+            Dismiss
+          </button>
+        </div>
+      )}
+
+      {loading ? (
+        <div className="space-y-3">
+          {Array.from({ length: 3 }).map((_, i) => (
+            <div key={i} className="animate-pulse h-16 rounded-lg bg-gray-200" />
+          ))}
+        </div>
+      ) : fills.length === 0 ? (
+        <p className="text-sm text-center text-gray-500 py-4">No fills recorded yet.</p>
+      ) : (
+        <div className="space-y-3">
+          {fills.map((fill) => (
+            <div key={fill._id} className="rounded-lg border p-4">
+              <div className="flex items-start justify-between gap-4">
+                <div className="flex-1 min-w-0">
+                  <div className="flex items-center gap-2 mb-1">
+                    <span className="font-medium text-gray-900">{fill.regimenName}</span>
+                    <span
+                      className={`rounded-full px-2 py-0.5 text-xs font-medium ${STATUS_COLORS[fill.status] ?? STATUS_COLORS['completed']}`}
+                    >
+                      {STATUS_LABELS[fill.status] ?? fill.status}
+                    </span>
+                  </div>
+                  <p className="text-sm text-gray-500">
+                    {fill.numberOfDays} day{fill.numberOfDays !== 1 ? 's' : ''} &bull;{' '}
+                    {fill.items.length} medicine{fill.items.length !== 1 ? 's' : ''} &bull;{' '}
+                    {formatDate(fill.fillDate)}
+                  </p>
+                  {fill.notes && (
+                    <p className="text-xs text-gray-400 mt-1">{fill.notes}</p>
+                  )}
+                  <div className="flex flex-wrap gap-1 mt-2">
+                    {fill.items.map((item, i) => (
+                      <span
+                        key={i}
+                        className={`rounded-full px-2 py-0.5 text-xs ${
+                          item.wasShort
+                            ? 'bg-yellow-50 text-yellow-700'
+                            : 'bg-blue-50 text-blue-700'
+                        }`}
+                      >
+                        {item.medicineName}: {item.quantityTaken}/{item.quantityNeeded}
+                        {item.wasShort ? ' (short)' : ''}
+                      </span>
+                    ))}
+                  </div>
+                </div>
+                {fill.status !== OrganizerFillStatus.REVERSED && (
+                  <button
+                    onClick={() => handleUndo(fill._id)}
+                    className="shrink-0 rounded-lg border border-red-200 px-3 py-1.5 text-xs font-medium text-red-600 hover:bg-red-50 transition-colors"
+                  >
+                    Undo
+                  </button>
+                )}
+              </div>
+            </div>
+          ))}
+        </div>
+      )}
+    </div>
+  );
+}
+
+// --- Main component ---
+
+export function OrganizerTab({ householdId }: { householdId: string }) {
+  const [regimens, setRegimens] = useState<Regimen[]>([]);
+  const [regimensLoading, setRegimensLoading] = useState(true);
+  const [fillRefreshKey, setFillRefreshKey] = useState(0);
+
+  useEffect(() => {
+    listRegimens(householdId, { limit: 100 })
+      .then((r) => setRegimens(r.data))
+      .catch(() => {})
+      .finally(() => setRegimensLoading(false));
+  }, [householdId]);
+
+  function handleFilled() {
+    setFillRefreshKey((k) => k + 1);
+  }
+
+  return (
+    <div className="space-y-6">
+      {regimensLoading ? (
+        <div className="animate-pulse rounded-xl border bg-white p-6 h-40" />
+      ) : (
+        <FillWizard
+          householdId={householdId}
+          regimens={regimens}
+          onFilled={handleFilled}
+        />
+      )}
+      <FillHistory householdId={householdId} refreshKey={fillRefreshKey} />
+    </div>
+  );
+}
diff --git a/packages/web/src/app/(dashboard)/medicines/RegimensTab.tsx b/packages/web/src/app/(dashboard)/medicines/RegimensTab.tsx
new file mode 100644
index 0000000..2d4ccd4
--- /dev/null
+++ b/packages/web/src/app/(dashboard)/medicines/RegimensTab.tsx
@@ -0,0 +1,722 @@
+'use client';
+
+import { useState, useEffect, useCallback } from 'react';
+import {
+  listRegimens,
+  createRegimen,
+  updateRegimen,
+  deleteRegimen,
+  getBurnRates,
+} from '@/services/regimens';
+import { listMedicines } from '@/services/medicines';
+import {
+  DosageFrequency,
+  TimeOfDay,
+  DosageUnit,
+  MedicineForm,
+  allowedUnitsForForm,
+  defaultUnitForForm,
+} from '@meshitrack/shared';
+import type { CreateRegimenInput } from '@meshitrack/shared';
+import type { z } from 'zod/v4';
+import type {
+  RegimenResponseSchema,
+  RegimenMedicationInputSchema,
+  BurnRateItemSchema,
+} from '@meshitrack/shared';
+
+type Regimen = z.infer<typeof RegimenResponseSchema>;
+type MedicationInput = z.infer<typeof RegimenMedicationInputSchema>;
+type BurnRateItem = z.infer<typeof BurnRateItemSchema>;
+
+type MedicineOption = {
+  _id: string;
+  name: string;
+  strength: number;
+  strengthUnit: string;
+  form: MedicineForm;
+};
+
+const FREQUENCY_LABELS: Record<string, string> = {
+  daily: 'Once daily',
+  twice_daily: 'Twice daily',
+  three_times_daily: 'Three times daily',
+  weekly: 'Weekly',
+  every_other_day: 'Every other day',
+  as_needed: 'As needed',
+  custom: 'Custom',
+};
+
+const TIME_LABELS: Record<string, string> = {
+  morning: 'Morning',
+  afternoon: 'Afternoon',
+  evening: 'Evening',
+  bedtime: 'Bedtime',
+};
+
+const FORM_LABELS: Record<string, string> = {
+  tablet: 'Tablet',
+  capsule: 'Capsule',
+  liquid: 'Liquid',
+  injection: 'Injection',
+  other: 'Other',
+};
+
+function formatDate(dateStr: string): string {
+  return new Date(dateStr).toLocaleDateString();
+}
+
+// --- Medication sub-form row ---
+
+function MedicationRow({
+  medication,
+  index,
+  medicines,
+  onChange,
+  onRemove,
+}: {
+  medication: MedicationInput;
+  index: number;
+  medicines: MedicineOption[];
+  onChange: (index: number, updated: MedicationInput) => void;
+  onRemove: (index: number) => void;
+}) {
+  const selectedMed = medicines.find((m) => m._id === medication.medicineId);
+  const allowedUnits = selectedMed
+    ? allowedUnitsForForm(selectedMed.form)
+    : Object.values(DosageUnit);
+
+  function handleMedicineChange(medicineId: string) {
+    const med = medicines.find((m) => m._id === medicineId);
+    const newUnit = med ? defaultUnitForForm(med.form) : DosageUnit.TABLET;
+    onChange(index, { ...medication, medicineId, dosageUnit: newUnit });
+  }
+
+  return (
+    <div className="rounded-lg border bg-gray-50 p-4 space-y-3">
+      <div className="flex items-start justify-between gap-2">
+        <span className="text-sm font-medium text-gray-600">Medication {index + 1}</span>
+        <button
+          type="button"
+          onClick={() => onRemove(index)}
+          className="rounded p-1 text-gray-400 hover:text-red-600 hover:bg-red-50 transition-colors"
+          title="Remove medication"
+        >
+          <svg className="h-4 w-4" fill="none" stroke="currentColor" viewBox="0 0 24 24">
+            <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M6 18L18 6M6 6l12 12" />
+          </svg>
+        </button>
+      </div>
+
+      <div className="grid grid-cols-1 gap-3 md:grid-cols-2">
+        <div>
+          <label className="block text-xs font-medium text-gray-700 mb-1">Medicine</label>
+          <select
+            required
+            value={medication.medicineId}
+            onChange={(e) => handleMedicineChange(e.target.value)}
+            className="w-full rounded-lg border px-3 py-2 text-sm focus:border-primary-500 focus:ring-1 focus:ring-primary-500 focus:outline-none"
+          >
+            <option value="">Select medicine...</option>
+            {medicines.map((m) => (
+              <option key={m._id} value={m._id}>
+                {m.name} {m.strength} {m.strengthUnit} ({FORM_LABELS[m.form] ?? m.form})
+              </option>
+            ))}
+          </select>
+        </div>
+
+        <div className="flex gap-2">
+          <div className="flex-1">
+            <label className="block text-xs font-medium text-gray-700 mb-1">Dosage</label>
+            <input
+              type="number"
+              required
+              min={0.01}
+              step="any"
+              value={medication.dosage || ''}
+              onChange={(e) => onChange(index, { ...medication, dosage: Number(e.target.value) })}
+              className="w-full rounded-lg border px-3 py-2 text-sm focus:border-primary-500 focus:ring-1 focus:ring-primary-500 focus:outline-none"
+            />
+          </div>
+          <div className="flex-1">
+            <label className="block text-xs font-medium text-gray-700 mb-1">Unit</label>
+            <select
+              value={medication.dosageUnit}
+              onChange={(e) =>
+                onChange(index, { ...medication, dosageUnit: e.target.value as DosageUnit })
+              }
+              className="w-full rounded-lg border px-3 py-2 text-sm focus:border-primary-500 focus:ring-1 focus:ring-primary-500 focus:outline-none"
+            >
+              {allowedUnits.map((u) => (
+                <option key={u} value={u}>
+                  {u}
+                </option>
+              ))}
+            </select>
+          </div>
+        </div>
+
+        <div>
+          <label className="block text-xs font-medium text-gray-700 mb-1">Frequency</label>
+          <select
+            value={medication.frequency}
+            onChange={(e) =>
+              onChange(index, {
+                ...medication,
+                frequency: e.target.value as DosageFrequency,
+                customFrequencyPerDay:
+                  e.target.value === DosageFrequency.CUSTOM
+                    ? (medication.customFrequencyPerDay ?? 1)
+                    : undefined,
+              })
+            }
+            className="w-full rounded-lg border px-3 py-2 text-sm focus:border-primary-500 focus:ring-1 focus:ring-primary-500 focus:outline-none"
+          >
+            {Object.values(DosageFrequency).map((f) => (
+              <option key={f} value={f}>
+                {FREQUENCY_LABELS[f] ?? f}
+              </option>
+            ))}
+          </select>
+        </div>
+
+        {medication.frequency === DosageFrequency.CUSTOM && (
+          <div>
+            <label className="block text-xs font-medium text-gray-700 mb-1">Times per day</label>
+            <input
+              type="number"
+              required
+              min={1}
+              step={1}
+              value={medication.customFrequencyPerDay ?? ''}
+              onChange={(e) =>
+                onChange(index, { ...medication, customFrequencyPerDay: Number(e.target.value) })
+              }
+              className="w-full rounded-lg border px-3 py-2 text-sm focus:border-primary-500 focus:ring-1 focus:ring-primary-500 focus:outline-none"
+            />
+          </div>
+        )}
+
+        <div>
+          <label className="block text-xs font-medium text-gray-700 mb-1">
+            Time of day (optional)
+          </label>
+          <select
+            value={medication.timeOfDay ?? ''}
+            onChange={(e) =>
+              onChange(index, {
+                ...medication,
+                timeOfDay: e.target.value ? (e.target.value as TimeOfDay) : undefined,
+              })
+            }
+            className="w-full rounded-lg border px-3 py-2 text-sm focus:border-primary-500 focus:ring-1 focus:ring-primary-500 focus:outline-none"
+          >
+            <option value="">Any time</option>
+            {Object.values(TimeOfDay).map((t) => (
+              <option key={t} value={t}>
+                {TIME_LABELS[t] ?? t}
+              </option>
+            ))}
+          </select>
+        </div>
+
+        <div>
+          <label className="block text-xs font-medium text-gray-700 mb-1">
+            Instructions (optional)
+          </label>
+          <input
+            type="text"
+            maxLength={500}
+            value={medication.instructions ?? ''}
+            onChange={(e) =>
+              onChange(index, { ...medication, instructions: e.target.value || undefined })
+            }
+            placeholder="e.g. Take with food"
+            className="w-full rounded-lg border px-3 py-2 text-sm focus:border-primary-500 focus:ring-1 focus:ring-primary-500 focus:outline-none"
+          />
+        </div>
+      </div>
+    </div>
+  );
+}
+
+// --- Regimen create / edit form ---
+
+function emptyMedication(): MedicationInput {
+  return {
+    medicineId: '',
+    dosage: 1,
+    dosageUnit: DosageUnit.TABLET,
+    frequency: DosageFrequency.DAILY,
+  };
+}
+
+function RegimenForm({
+  householdId,
+  medicines,
+  initial,
+  onSaved,
+  onCancel,
+}: {
+  householdId: string;
+  medicines: MedicineOption[];
+  initial?: Regimen;
+  onSaved: () => void;
+  onCancel: () => void;
+}) {
+  const [name, setName] = useState(initial?.name ?? '');
+  const [isActive, setIsActive] = useState(initial?.isActive ?? true);
+  const [medications, setMedications] = useState<MedicationInput[]>(
+    initial?.medications.map((m) => ({
+      medicineId: m.medicineId,
+      dosage: m.dosage,
+      dosageUnit: m.dosageUnit as DosageUnit,
+      frequency: m.frequency as DosageFrequency,
+      customFrequencyPerDay: m.customFrequencyPerDay,
+      timeOfDay: m.timeOfDay as TimeOfDay | undefined,
+      instructions: m.instructions,
+    })) ?? [emptyMedication()],
+  );
+  const [submitting, setSubmitting] = useState(false);
+  const [error, setError] = useState('');
+
+  function updateMedication(index: number, updated: MedicationInput) {
+    setMedications((prev) => prev.map((m, i) => (i === index ? updated : m)));
+  }
+
+  function removeMedication(index: number) {
+    setMedications((prev) => prev.filter((_, i) => i !== index));
+  }
+
+  function addMedication() {
+    setMedications((prev) => [...prev, emptyMedication()]);
+  }
+
+  async function handleSubmit(e: React.FormEvent) {
+    e.preventDefault();
+    if (medications.length === 0) {
+      setError('At least one medication is required.');
+      return;
+    }
+    setError('');
+    setSubmitting(true);
+    try {
+      const payload: CreateRegimenInput = { name: name.trim(), isActive, medications };
+      if (initial) {
+        await updateRegimen(householdId, initial._id, payload);
+      } else {
+        await createRegimen(householdId, payload);
+      }
+      onSaved();
+    } catch (err) {
+      setError(err instanceof Error ? err.message : 'Failed to save regimen');
+    } finally {
+      setSubmitting(false);
+    }
+  }
+
+  return (
+    <div className="mb-6 rounded-xl border bg-white p-6 shadow-sm">
+      <h2 className="text-lg font-semibold mb-4">{initial ? 'Edit Regimen' : 'New Regimen'}</h2>
+      {error && (
+        <div className="mb-4 rounded-lg bg-red-50 border border-red-200 p-3 text-sm text-red-700">
+          {error}
+        </div>
+      )}
+      <form onSubmit={handleSubmit} className="space-y-5">
+        <div className="grid grid-cols-1 gap-4 md:grid-cols-2">
+          <div>
+            <label className="block text-sm font-medium text-gray-700 mb-1">Name</label>
+            <input
+              type="text"
+              required
+              maxLength={200}
+              value={name}
+              onChange={(e) => setName(e.target.value)}
+              placeholder="e.g. Morning routine"
+              className="w-full rounded-lg border px-3 py-2 text-sm focus:border-primary-500 focus:ring-1 focus:ring-primary-500 focus:outline-none"
+            />
+          </div>
+          <div className="flex items-center gap-3 pt-6">
+            <input
+              type="checkbox"
+              id="isActive"
+              checked={isActive}
+              onChange={(e) => setIsActive(e.target.checked)}
+              className="h-4 w-4 rounded border-gray-300 text-primary-600 focus:ring-primary-500"
+            />
+            <label htmlFor="isActive" className="text-sm font-medium text-gray-700">
+              Active
+            </label>
+          </div>
+        </div>
+
+        <div>
+          <div className="flex items-center justify-between mb-3">
+            <h3 className="text-sm font-semibold text-gray-800">Medications</h3>
+            <button
+              type="button"
+              onClick={addMedication}
+              className="rounded-lg border border-primary-600 px-3 py-1.5 text-xs font-medium text-primary-600 hover:bg-primary-50 transition-colors"
+            >
+              + Add medication
+            </button>
+          </div>
+          {medications.length === 0 ? (
+            <p className="text-sm text-gray-500 italic">No medications added yet.</p>
+          ) : (
+            <div className="space-y-3">
+              {medications.map((med, i) => (
+                <MedicationRow
+                  key={i}
+                  index={i}
+                  medication={med}
+                  medicines={medicines}
+                  onChange={updateMedication}
+                  onRemove={removeMedication}
+                />
+              ))}
+            </div>
+          )}
+        </div>
+
+        <div className="flex gap-3 pt-2">
+          <button
+            type="submit"
+            disabled={submitting}
+            className="rounded-lg bg-primary-600 px-4 py-2 text-sm font-medium text-white hover:bg-primary-700 disabled:opacity-50 transition-colors"
+          >
+            {submitting ? 'Saving...' : initial ? 'Save changes' : 'Create regimen'}
+          </button>
+          <button
+            type="button"
+            onClick={onCancel}
+            className="rounded-lg border px-4 py-2 text-sm font-medium hover:bg-gray-50 transition-colors"
+          >
+            Cancel
+          </button>
+        </div>
+      </form>
+    </div>
+  );
+}
+
+// --- Burn rate table ---
+
+function BurnRateTable({ burnRates }: { burnRates: BurnRateItem[] }) {
+  if (burnRates.length === 0) {
+    return (
+      <p className="text-sm text-gray-500">
+        No active regimens with cabinet stock to calculate burn rates.
+      </p>
+    );
+  }
+
+  return (
+    <div className="overflow-x-auto">
+      <table className="w-full text-sm">
+        <thead>
+          <tr className="border-b text-left text-gray-500">
+            <th className="pb-2 font-medium">Medicine</th>
+            <th className="pb-2 font-medium text-right">Daily use</th>
+            <th className="pb-2 font-medium text-right">In cabinet</th>
+            <th className="pb-2 font-medium text-right">Days left</th>
+            <th className="pb-2 font-medium text-right">Monthly cost</th>
+          </tr>
+        </thead>
+        <tbody className="divide-y divide-gray-100">
+          {burnRates.map((item) => {
+            const daysLeft = item.daysUntilEmpty;
+            const daysColor =
+              daysLeft === null
+                ? 'text-gray-400'
+                : daysLeft <= 7
+                  ? 'text-red-600 font-semibold'
+                  : daysLeft <= 30
+                    ? 'text-yellow-600'
+                    : 'text-green-600';
+
+            return (
+              <tr key={item.medicineId} className="py-2">
+                <td className="py-2 font-medium text-gray-900">{item.medicineName}</td>
+                <td className="py-2 text-right text-gray-600">
+                  {item.dailyConsumption.toFixed(2)}
+                </td>
+                <td className="py-2 text-right text-gray-600">{item.totalInCabinet}</td>
+                <td className={`py-2 text-right ${daysColor}`}>
+                  {daysLeft !== null ? daysLeft : '-'}
+                </td>
+                <td className="py-2 text-right text-gray-600">
+                  {item.projectedMonthlyCost !== null
+                    ? `${item.currency ?? ''} ${item.projectedMonthlyCost.toFixed(2)}`.trim()
+                    : '-'}
+                </td>
+              </tr>
+            );
+          })}
+        </tbody>
+      </table>
+    </div>
+  );
+}
+
+// --- Main component ---
+
+export function RegimensTab({ householdId }: { householdId: string }) {
+  const [regimens, setRegimens] = useState<Regimen[]>([]);
+  const [loading, setLoading] = useState(true);
+  const [error, setError] = useState('');
+  const [medicines, setMedicines] = useState<MedicineOption[]>([]);
+  const [showForm, setShowForm] = useState(false);
+  const [editingRegimen, setEditingRegimen] = useState<Regimen | null>(null);
+  const [filterActive, setFilterActive] = useState<'all' | 'active' | 'inactive'>('all');
+  const [burnRates, setBurnRates] = useState<BurnRateItem[]>([]);
+  const [showBurnRate, setShowBurnRate] = useState(false);
+  const [burnRateLoading, setBurnRateLoading] = useState(false);
+
+  const fetchRegimens = useCallback(async () => {
+    setLoading(true);
+    try {
+      const query =
+        filterActive === 'active'
+          ? { isActive: true }
+          : filterActive === 'inactive'
+            ? { isActive: false }
+            : {};
+      const result = await listRegimens(householdId, { ...query, limit: 50 });
+      setRegimens(result.data);
+    } catch (err) {
+      setError(err instanceof Error ? err.message : 'Failed to load regimens');
+    } finally {
+      setLoading(false);
+    }
+  }, [householdId, filterActive]);
+
+  useEffect(() => {
+    fetchRegimens();
+  }, [fetchRegimens]);
+
+  // Medicines are needed for the form
+  useEffect(() => {
+    listMedicines(householdId, { limit: 100 })
+      .then((r) => setMedicines(r.data as MedicineOption[]))
+      .catch(() => {});
+  }, [householdId]);
+
+  async function handleDelete(id: string, name: string) {
+    if (!confirm(`Delete regimen "${name}"?`)) return;
+    try {
+      await deleteRegimen(householdId, id);
+      setRegimens((prev) => prev.filter((r) => r._id !== id));
+    } catch (err) {
+      setError(err instanceof Error ? err.message : 'Failed to delete');
+    }
+  }
+
+  async function handleToggleActive(regimen: Regimen) {
+    try {
+      const updated = await updateRegimen(householdId, regimen._id, {
+        isActive: !regimen.isActive,
+      });
+      setRegimens((prev) => prev.map((r) => (r._id === regimen._id ? updated : r)));
+    } catch (err) {
+      setError(err instanceof Error ? err.message : 'Failed to update');
+    }
+  }
+
+  async function handleShowBurnRate() {
+    setShowBurnRate((prev) => !prev);
+    if (!showBurnRate && burnRates.length === 0) {
+      setBurnRateLoading(true);
+      try {
+        const result = await getBurnRates(householdId);
+        setBurnRates(result.data);
+      } catch (err) {
+        setError(err instanceof Error ? err.message : 'Failed to load burn rates');
+      } finally {
+        setBurnRateLoading(false);
+      }
+    }
+  }
+
+  const isFormOpen = showForm || editingRegimen !== null;
+
+  return (
+    <div>
+      <div className="flex items-center justify-between mb-4">
+        <div className="flex items-center gap-3">
+          <select
+            value={filterActive}
+            onChange={(e) => setFilterActive(e.target.value as 'all' | 'active' | 'inactive')}
+            className="rounded-lg border px-3 py-2 text-sm focus:border-primary-500 focus:ring-1 focus:ring-primary-500 focus:outline-none"
+          >
+            <option value="all">All regimens</option>
+            <option value="active">Active</option>
+            <option value="inactive">Inactive</option>
+          </select>
+          <button
+            onClick={handleShowBurnRate}
+            className="rounded-lg border px-4 py-2 text-sm font-medium hover:bg-gray-50 transition-colors"
+          >
+            {showBurnRate ? 'Hide burn rate' : 'Burn rate'}
+          </button>
+        </div>
+        <button
+          onClick={() => {
+            setEditingRegimen(null);
+            setShowForm(!showForm);
+          }}
+          className="rounded-lg bg-primary-600 px-4 py-2 text-sm font-medium text-white hover:bg-primary-700 transition-colors"
+        >
+          {showForm ? 'Cancel' : 'New Regimen'}
+        </button>
+      </div>
+
+      {error && (
+        <div className="mb-4 rounded-lg bg-red-50 border border-red-200 p-3 text-sm text-red-700">
+          {error}
+          <button onClick={() => setError('')} className="ml-2 underline">
+            Dismiss
+          </button>
+        </div>
+      )}
+
+      {showBurnRate && (
+        <div className="mb-6 rounded-xl border bg-white p-6 shadow-sm">
+          <h2 className="text-lg font-semibold mb-4">Burn Rate &amp; Spending Projections</h2>
+          {burnRateLoading ? (
+            <div className="animate-pulse space-y-2">
+              <div className="h-6 w-full rounded bg-gray-200" />
+              <div className="h-6 w-full rounded bg-gray-200" />
+            </div>
+          ) : (
+            <BurnRateTable burnRates={burnRates} />
+          )}
+        </div>
+      )}
+
+      {showForm && !editingRegimen && (
+        <RegimenForm
+          householdId={householdId}
+          medicines={medicines}
+          onSaved={() => {
+            setShowForm(false);
+            fetchRegimens();
+            setBurnRates([]);
+          }}
+          onCancel={() => setShowForm(false)}
+        />
+      )}
+
+      {editingRegimen && (
+        <RegimenForm
+          householdId={householdId}
+          medicines={medicines}
+          initial={editingRegimen}
+          onSaved={() => {
+            setEditingRegimen(null);
+            fetchRegimens();
+            setBurnRates([]);
+          }}
+          onCancel={() => setEditingRegimen(null)}
+        />
+      )}
+
+      {loading ? (
+        <div className="space-y-3">
+          {Array.from({ length: 3 }).map((_, i) => (
+            <div key={i} className="animate-pulse rounded-xl border bg-white p-4 h-24" />
+          ))}
+        </div>
+      ) : regimens.length === 0 ? (
+        <div className="rounded-xl border bg-white p-6 shadow-sm text-center text-gray-500">
+          {filterActive !== 'all'
+            ? `No ${filterActive} regimens found.`
+            : isFormOpen
+              ? null
+              : 'No regimens yet. Create your first medication schedule above.'}
+        </div>
+      ) : (
+        <div className="space-y-3">
+          {regimens.map((regimen) => (
+            <div key={regimen._id} className="rounded-xl border bg-white p-4 shadow-sm">
+              <div className="flex items-start justify-between gap-4">
+                <div className="flex-1 min-w-0">
+                  <div className="flex items-center gap-2 mb-1">
+                    <h3 className="font-semibold text-gray-900">{regimen.name}</h3>
+                    <span
+                      className={`rounded-full px-2 py-0.5 text-xs font-medium ${
+                        regimen.isActive
+                          ? 'bg-green-100 text-green-700'
+                          : 'bg-gray-100 text-gray-500'
+                      }`}
+                    >
+                      {regimen.isActive ? 'Active' : 'Inactive'}
+                    </span>
+                  </div>
+                  <p className="text-sm text-gray-500 mb-2">
+                    {regimen.medications.length} medication
+                    {regimen.medications.length !== 1 ? 's' : ''}
+                  </p>
+                  <div className="flex flex-wrap gap-1">
+                    {regimen.medications.map((med, i) => (
+                      <span
+                        key={i}
+                        className="rounded-full bg-blue-50 px-2 py-0.5 text-xs text-blue-700"
+                      >
+                        {med.medicineName} — {med.dosage} {med.dosageUnit} (
+                        {FREQUENCY_LABELS[med.frequency] ?? med.frequency})
+                      </span>
+                    ))}
+                  </div>
+                  <p className="mt-2 text-xs text-gray-400">Created {formatDate(regimen.createdAt)}</p>
+                </div>
+                <div className="flex items-center gap-2 shrink-0">
+                  <button
+                    onClick={() => handleToggleActive(regimen)}
+                    className="rounded-lg border px-3 py-1.5 text-xs font-medium hover:bg-gray-50 transition-colors"
+                    title={regimen.isActive ? 'Deactivate' : 'Activate'}
+                  >
+                    {regimen.isActive ? 'Deactivate' : 'Activate'}
+                  </button>
+                  <button
+                    onClick={() => {
+                      setShowForm(false);
+                      setEditingRegimen(regimen);
+                    }}
+                    className="rounded p-1.5 text-gray-400 hover:text-primary-600 hover:bg-primary-50 transition-colors"
+                    title="Edit"
+                  >
+                    <svg className="h-4 w-4" fill="none" stroke="currentColor" viewBox="0 0 24 24">
+                      <path
+                        strokeLinecap="round"
+                        strokeLinejoin="round"
+                        strokeWidth={2}
+                        d="M11 5H6a2 2 0 00-2 2v11a2 2 0 002 2h11a2 2 0 002-2v-5m-1.414-9.414a2 2 0 112.828 2.828L11.828 15H9v-2.828l8.586-8.586z"
+                      />
+                    </svg>
+                  </button>
+                  <button
+                    onClick={() => handleDelete(regimen._id, regimen.name)}
+                    className="rounded p-1.5 text-gray-400 hover:text-red-600 hover:bg-red-50 transition-colors"
+                    title="Delete"
+                  >
+                    <svg className="h-4 w-4" fill="none" stroke="currentColor" viewBox="0 0 24 24">
+                      <path
+                        strokeLinecap="round"
+                        strokeLinejoin="round"
+                        strokeWidth={2}
+                        d="M19 7l-.867 12.142A2 2 0 0116.138 21H7.862a2 2 0 01-1.995-1.858L5 7m5 4v6m4-6v6m1-10V4a1 1 0 00-1-1h-4a1 1 0 00-1 1v3M4 7h16"
+                      />
+                    </svg>
+                  </button>
+                </div>
+              </div>
+            </div>
+          ))}
+        </div>
+      )}
+    </div>
+  );
+}
diff --git a/packages/web/src/app/(dashboard)/medicines/activity/page.tsx b/packages/web/src/app/(dashboard)/medicines/activity/page.tsx
new file mode 100644
index 0000000..a30ccd4
--- /dev/null
+++ b/packages/web/src/app/(dashboard)/medicines/activity/page.tsx
@@ -0,0 +1,51 @@
+'use client';
+
+import Link from 'next/link';
+import { useApi } from '@/lib/useApi';
+import { ActivityTab } from '../ActivityTab';
+
+export default function ActivityPage() {
+  const { householdId, isLoading: sessionLoading } = useApi();
+
+  if (sessionLoading) {
+    return (
+      <div>
+        <h1 className="text-2xl font-bold mb-4">Cabinet Activity</h1>
+        <div className="animate-pulse space-y-3">
+          <div className="h-40 rounded-xl bg-gray-200" />
+          <div className="h-40 rounded-xl bg-gray-200" />
+        </div>
+      </div>
+    );
+  }
+
+  if (!householdId) {
+    return (
+      <div>
+        <h1 className="text-2xl font-bold mb-4">Cabinet Activity</h1>
+        <div className="rounded-xl border bg-white p-6 shadow-sm">
+          <p className="text-gray-500">
+            You need to{' '}
+            <Link href="/settings" className="text-primary-600 underline">
+              create or join a household
+            </Link>{' '}
+            before viewing cabinet activity.
+          </p>
+        </div>
+      </div>
+    );
+  }
+
+  return (
+    <div>
+      <div className="flex items-center gap-3 mb-6">
+        <Link href="/medicines" className="text-sm text-gray-500 hover:text-gray-700">
+          Medicines
+        </Link>
+        <span className="text-gray-400">/</span>
+        <h1 className="text-2xl font-bold">Cabinet Activity</h1>
+      </div>
+      <ActivityTab householdId={householdId} />
+    </div>
+  );
+}
diff --git a/packages/web/src/app/(dashboard)/medicines/organizer/page.tsx b/packages/web/src/app/(dashboard)/medicines/organizer/page.tsx
new file mode 100644
index 0000000..db7609a
--- /dev/null
+++ b/packages/web/src/app/(dashboard)/medicines/organizer/page.tsx
@@ -0,0 +1,51 @@
+'use client';
+
+import Link from 'next/link';
+import { useApi } from '@/lib/useApi';
+import { OrganizerTab } from '../OrganizerTab';
+
+export default function OrganizerPage() {
+  const { householdId, isLoading: sessionLoading } = useApi();
+
+  if (sessionLoading) {
+    return (
+      <div>
+        <h1 className="text-2xl font-bold mb-4">Pill Organizer</h1>
+        <div className="animate-pulse space-y-3">
+          <div className="h-40 rounded-xl bg-gray-200" />
+          <div className="h-40 rounded-xl bg-gray-200" />
+        </div>
+      </div>
+    );
+  }
+
+  if (!householdId) {
+    return (
+      <div>
+        <h1 className="text-2xl font-bold mb-4">Pill Organizer</h1>
+        <div className="rounded-xl border bg-white p-6 shadow-sm">
+          <p className="text-gray-500">
+            You need to{' '}
+            <Link href="/settings" className="text-primary-600 underline">
+              create or join a household
+            </Link>{' '}
+            before using the pill organizer.
+          </p>
+        </div>
+      </div>
+    );
+  }
+
+  return (
+    <div>
+      <div className="flex items-center gap-3 mb-6">
+        <Link href="/medicines" className="text-sm text-gray-500 hover:text-gray-700">
+          Medicines
+        </Link>
+        <span className="text-gray-400">/</span>
+        <h1 className="text-2xl font-bold">Pill Organizer</h1>
+      </div>
+      <OrganizerTab householdId={householdId} />
+    </div>
+  );
+}
diff --git a/packages/web/src/app/(dashboard)/medicines/page.tsx b/packages/web/src/app/(dashboard)/medicines/page.tsx
index 962eca8..4eb6618 100644
--- a/packages/web/src/app/(dashboard)/medicines/page.tsx
+++ b/packages/web/src/app/(dashboard)/medicines/page.tsx
@@ -41,6 +41,21 @@ export default function MedicinesPage() {
           description="Track your medicine inventory, quantities and expiry dates"
           href="/medicines/cabinet"
         />
+        <SectionCard
+          title="Regimens"
+          description="Define daily medication schedules and track dosage frequency"
+          href="/medicines/regimens"
+        />
+        <SectionCard
+          title="Organizer"
+          description="Fill your pill organizer and track cabinet usage"
+          href="/medicines/organizer"
+        />
+        <SectionCard
+          title="Activity"
+          description="View cabinet event history and spending summaries"
+          href="/medicines/activity"
+        />
       </div>
     </div>
   );
@@ -73,6 +88,9 @@ function PageSkeleton() {
       <div className="animate-pulse grid grid-cols-1 gap-6 md:grid-cols-2 lg:grid-cols-3">
         <div className="h-24 rounded-xl bg-gray-200" />
         <div className="h-24 rounded-xl bg-gray-200" />
+        <div className="h-24 rounded-xl bg-gray-200" />
+        <div className="h-24 rounded-xl bg-gray-200" />
+        <div className="h-24 rounded-xl bg-gray-200" />
       </div>
     </div>
   );
diff --git a/packages/web/src/app/(dashboard)/medicines/regimens/page.tsx b/packages/web/src/app/(dashboard)/medicines/regimens/page.tsx
new file mode 100644
index 0000000..7e711ec
--- /dev/null
+++ b/packages/web/src/app/(dashboard)/medicines/regimens/page.tsx
@@ -0,0 +1,52 @@
+'use client';
+
+import Link from 'next/link';
+import { useApi } from '@/lib/useApi';
+import { RegimensTab } from '../RegimensTab';
+
+export default function RegimensPage() {
+  const { householdId, isLoading: sessionLoading } = useApi();
+
+  if (sessionLoading) {
+    return (
+      <div>
+        <h1 className="text-2xl font-bold mb-4">Regimens</h1>
+        <div className="animate-pulse space-y-3">
+          <div className="h-10 w-64 rounded-lg bg-gray-200" />
+          <div className="h-24 rounded-xl bg-gray-200" />
+          <div className="h-24 rounded-xl bg-gray-200" />
+        </div>
+      </div>
+    );
+  }
+
+  if (!householdId) {
+    return (
+      <div>
+        <h1 className="text-2xl font-bold mb-4">Regimens</h1>
+        <div className="rounded-xl border bg-white p-6 shadow-sm">
+          <p className="text-gray-500">
+            You need to{' '}
+            <Link href="/settings" className="text-primary-600 underline">
+              create or join a household
+            </Link>{' '}
+            before managing regimens.
+          </p>
+        </div>
+      </div>
+    );
+  }
+
+  return (
+    <div>
+      <div className="flex items-center gap-3 mb-6">
+        <Link href="/medicines" className="text-sm text-gray-500 hover:text-gray-700">
+          Medicines
+        </Link>
+        <span className="text-gray-400">/</span>
+        <h1 className="text-2xl font-bold">Regimens</h1>
+      </div>
+      <RegimensTab householdId={householdId} />
+    </div>
+  );
+}
diff --git a/packages/web/src/services/cabinet-events.ts b/packages/web/src/services/cabinet-events.ts
new file mode 100644
index 0000000..9942d26
--- /dev/null
+++ b/packages/web/src/services/cabinet-events.ts
@@ -0,0 +1,60 @@
+import { apiClient } from './api-client';
+import type { z } from 'zod/v4';
+import type {
+  CabinetEventListResponseSchema,
+  SpendingSummaryResponseSchema,
+} from '@meshitrack/shared';
+
+type CabinetEventListResponse = z.infer<typeof CabinetEventListResponseSchema>;
+type SpendingSummaryResponse = z.infer<typeof SpendingSummaryResponseSchema>;
+
+export async function listCabinetEvents(
+  householdId: string,
+  query?: {
+    medicineId?: string;
+    eventType?: string;
+    startDate?: string;
+    endDate?: string;
+    cursor?: string;
+    limit?: number;
+  },
+): Promise<CabinetEventListResponse> {
+  const params = new URLSearchParams();
+  if (query?.medicineId) params.set('medicineId', query.medicineId);
+  if (query?.eventType) params.set('eventType', query.eventType);
+  if (query?.startDate) params.set('startDate', query.startDate);
+  if (query?.endDate) params.set('endDate', query.endDate);
+  if (query?.cursor) params.set('cursor', query.cursor);
+  if (query?.limit) params.set('limit', String(query.limit));
+  const qs = params.toString();
+  return apiClient.get<CabinetEventListResponse>(
+    `/households/${householdId}/cabinet-events${qs ? `?${qs}` : ''}`,
+  );
+}
+
+export async function getEventsByItem(
+  householdId: string,
+  cabinetItemId: string,
+  query?: { cursor?: string; limit?: number },
+): Promise<CabinetEventListResponse> {
+  const params = new URLSearchParams();
+  if (query?.cursor) params.set('cursor', query.cursor);
+  if (query?.limit) params.set('limit', String(query.limit));
+  const qs = params.toString();
+  return apiClient.get<CabinetEventListResponse>(
+    `/households/${householdId}/cabinet-events/by-item/${cabinetItemId}${qs ? `?${qs}` : ''}`,
+  );
+}
+
+export async function getSpendingSummary(
+  householdId: string,
+  query?: { period?: string; medicineId?: string },
+): Promise<SpendingSummaryResponse> {
+  const params = new URLSearchParams();
+  if (query?.period) params.set('period', query.period);
+  if (query?.medicineId) params.set('medicineId', query.medicineId);
+  const qs = params.toString();
+  return apiClient.get<SpendingSummaryResponse>(
+    `/households/${householdId}/cabinet-events/spending-summary${qs ? `?${qs}` : ''}`,
+  );
+}
diff --git a/packages/web/src/services/organizer.ts b/packages/web/src/services/organizer.ts
new file mode 100644
index 0000000..fd58b16
--- /dev/null
+++ b/packages/web/src/services/organizer.ts
@@ -0,0 +1,55 @@
+import { apiClient } from './api-client';
+import type { z } from 'zod/v4';
+import type {
+  OrganizerFillListResponseSchema,
+  OrganizerFillResponseSchema,
+  OrganizerPreviewResponseSchema,
+  OrganizerFillSchema,
+  OrganizerPreviewSchema,
+} from '@meshitrack/shared';
+
+type OrganizerFillListResponse = z.infer<typeof OrganizerFillListResponseSchema>;
+type OrganizerFillResponse = z.infer<typeof OrganizerFillResponseSchema>;
+type OrganizerPreviewResponse = z.infer<typeof OrganizerPreviewResponseSchema>;
+type OrganizerFillInput = z.infer<typeof OrganizerFillSchema>;
+type OrganizerPreviewInput = z.infer<typeof OrganizerPreviewSchema>;
+
+export async function listFills(
+  householdId: string,
+  query?: { regimenId?: string; status?: string; cursor?: string; limit?: number },
+): Promise<OrganizerFillListResponse> {
+  const params = new URLSearchParams();
+  if (query?.regimenId) params.set('regimenId', query.regimenId);
+  if (query?.status) params.set('status', query.status);
+  if (query?.cursor) params.set('cursor', query.cursor);
+  if (query?.limit) params.set('limit', String(query.limit));
+  const qs = params.toString();
+  return apiClient.get<OrganizerFillListResponse>(
+    `/households/${householdId}/organizer/fills${qs ? `?${qs}` : ''}`,
+  );
+}
+
+export async function getFill(householdId: string, id: string): Promise<OrganizerFillResponse> {
+  return apiClient.get<OrganizerFillResponse>(`/households/${householdId}/organizer/fills/${id}`);
+}
+
+export async function previewFill(
+  householdId: string,
+  data: OrganizerPreviewInput,
+): Promise<OrganizerPreviewResponse> {
+  return apiClient.post<OrganizerPreviewResponse>(`/households/${householdId}/organizer/preview`, data);
+}
+
+export async function executeFill(
+  householdId: string,
+  data: OrganizerFillInput,
+): Promise<OrganizerFillResponse> {
+  return apiClient.post<OrganizerFillResponse>(`/households/${householdId}/organizer/fill`, data);
+}
+
+export async function undoFill(householdId: string, fillId: string): Promise<OrganizerFillResponse> {
+  return apiClient.post<OrganizerFillResponse>(
+    `/households/${householdId}/organizer/fills/${fillId}/undo`,
+    {},
+  );
+}
diff --git a/packages/web/src/services/regimens.ts b/packages/web/src/services/regimens.ts
new file mode 100644
index 0000000..fa476ef
--- /dev/null
+++ b/packages/web/src/services/regimens.ts
@@ -0,0 +1,51 @@
+import { apiClient } from './api-client';
+import type { z } from 'zod/v4';
+import type {
+  RegimenResponseSchema,
+  RegimenListResponseSchema,
+  BurnRateResponseSchema,
+  CreateRegimenSchema,
+  UpdateRegimenSchema,
+} from '@meshitrack/shared';
+
+type RegimenResponse = z.infer<typeof RegimenResponseSchema>;
+type RegimenListResponse = z.infer<typeof RegimenListResponseSchema>;
+type BurnRateResponse = z.infer<typeof BurnRateResponseSchema>;
+type CreateRegimenInput = z.infer<typeof CreateRegimenSchema>;
+type UpdateRegimenInput = z.infer<typeof UpdateRegimenSchema>;
+
+export async function listRegimens(
+  householdId: string,
+  query?: { isActive?: boolean; cursor?: string; limit?: number },
+): Promise<RegimenListResponse> {
+  const params = new URLSearchParams();
+  if (query?.isActive !== undefined) params.set('isActive', String(query.isActive));
+  if (query?.cursor) params.set('cursor', query.cursor);
+  if (query?.limit) params.set('limit', String(query.limit));
+  const qs = params.toString();
+  return apiClient.get<RegimenListResponse>(`/households/${householdId}/regimens${qs ? `?${qs}` : ''}`);
+}
+
+export async function getRegimen(householdId: string, id: string): Promise<RegimenResponse> {
+  return apiClient.get<RegimenResponse>(`/households/${householdId}/regimens/${id}`);
+}
+
+export async function getBurnRates(householdId: string): Promise<BurnRateResponse> {
+  return apiClient.get<BurnRateResponse>(`/households/${householdId}/regimens/burn-rate`);
+}
+
+export async function createRegimen(householdId: string, data: CreateRegimenInput): Promise<RegimenResponse> {
+  return apiClient.post<RegimenResponse>(`/households/${householdId}/regimens`, data);
+}
+
+export async function updateRegimen(
+  householdId: string,
+  id: string,
+  data: UpdateRegimenInput,
+): Promise<RegimenResponse> {
+  return apiClient.patch<RegimenResponse>(`/households/${householdId}/regimens/${id}`, data);
+}
+
+export async function deleteRegimen(householdId: string, id: string): Promise<void> {
+  return apiClient.delete<void>(`/households/${householdId}/regimens/${id}`);
+}