diff --git a/src/app/api/illness/episodes/[id]/correlation/route.ts b/src/app/api/illness/episodes/[id]/correlation/route.ts
index a315f69ae..c0f647364 100644
--- a/src/app/api/illness/episodes/[id]/correlation/route.ts
+++ b/src/app/api/illness/episodes/[id]/correlation/route.ts
@@ -21,6 +21,7 @@ import { annotate } from "@/lib/logging/context";
 import { apiSuccess, apiError } from "@/lib/api-response";
 import { requireIllnessEnabled } from "@/lib/illness/gate";
 import { computeEpisodeCorrelation } from "@/lib/illness/correlation-read";
+import { notifyIllnessRedFlag } from "@/lib/illness/red-flag-notify";
 import { DEFAULT_TIMEZONE } from "@/lib/mood/date-key";
 
 type RouteParams = { params: Promise<{ id: string }> };
@@ -74,6 +75,18 @@ export const GET = apiHandler(
       },
     });
 
+    // v1.18.4 — bridge the red-flag escalation to an urgent push. Owner-scoped
+    // (the episode is already confirmed to belong to `user.id`) + module-gated
+    // (the illness gate above). Awaited but internally de-duped + no-throw, so a
+    // re-read never re-fires and a notification hiccup can't fail the read.
+    if (derived.status === "ok" && derived.value.redFlags.length > 0) {
+      await notifyIllnessRedFlag({
+        userId: user.id,
+        episodeId: id,
+        redFlags: derived.value.redFlags,
+      });
+    }
+
     return apiSuccess({
       episodeId: id,
       status: derived.status,
diff --git a/src/lib/illness/__tests__/red-flag-notify.test.ts b/src/lib/illness/__tests__/red-flag-notify.test.ts
new file mode 100644
index 000000000..9a852ca9c
--- /dev/null
+++ b/src/lib/illness/__tests__/red-flag-notify.test.ts
@@ -0,0 +1,119 @@
+/**
+ * v1.18.4 — illness red-flag escalation push.
+ *
+ * Pins: empty red-flags is a no-op; a fresh red flag dispatches an URGENT
+ * localised SYSTEM_ALERT; a recent ledger row de-dupes (no re-fire); the
+ * fever reason is preferred for the body; failures never throw.
+ */
+import { afterEach, beforeEach, describe, expect, it, vi } from "vitest";
+
+const findFirstMock = vi.fn();
+const createMock = vi.fn();
+const dispatchMock = vi.fn();
+
+vi.mock("@/lib/db", () => ({
+  prisma: {
+    pushAttempt: {
+      findFirst: (...a: unknown[]) => findFirstMock(...a),
+      create: (...a: unknown[]) => createMock(...a),
+    },
+  },
+}));
+
+vi.mock("@/lib/logging/context", () => ({
+  getEvent: () => ({ addMeta: vi.fn(), addWarning: vi.fn() }),
+}));
+
+vi.mock("@/lib/notifications/dispatch-localised", () => ({
+  dispatchLocalisedNotification: (...a: unknown[]) => dispatchMock(...a),
+}));
+
+import { notifyIllnessRedFlag } from "../red-flag-notify";
+import type { IllnessRedFlag } from "../correlation";
+
+const spo2Flag: IllnessRedFlag = {
+  type: "SPO2" as never,
+  reason: "sustained_low_spo2",
+  worstValue: 89,
+  days: 3,
+};
+const feverFlag: IllnessRedFlag = {
+  type: "BODY_TEMPERATURE" as never,
+  reason: "sustained_fever",
+  worstValue: 39.1,
+  days: 3,
+};
+
+beforeEach(() => {
+  findFirstMock.mockReset().mockResolvedValue(null);
+  createMock.mockReset().mockResolvedValue({});
+  dispatchMock.mockReset().mockResolvedValue(undefined);
+});
+
+afterEach(() => vi.clearAllMocks());
+
+describe("notifyIllnessRedFlag", () => {
+  it("no-op when there are no red flags", async () => {
+    await notifyIllnessRedFlag({ userId: "u1", episodeId: "e1", redFlags: [] });
+    expect(dispatchMock).not.toHaveBeenCalled();
+    expect(findFirstMock).not.toHaveBeenCalled();
+  });
+
+  it("dispatches an URGENT SYSTEM_ALERT for a fresh red flag", async () => {
+    await notifyIllnessRedFlag({
+      userId: "u1",
+      episodeId: "e1",
+      redFlags: [spo2Flag],
+    });
+    expect(dispatchMock).toHaveBeenCalledTimes(1);
+    const opts = dispatchMock.mock.calls[0][0];
+    expect(opts.urgent).toBe(true);
+    expect(opts.eventType).toBe("SYSTEM_ALERT");
+    expect(opts.userId).toBe("u1");
+    expect(opts.titleKey).toBe("illness.correlation.redFlagTitle");
+    expect(opts.messageKey).toBe("illness.correlation.redFlagSpo2");
+  });
+
+  it("prefers the fever reason for the body when both flags fire", async () => {
+    await notifyIllnessRedFlag({
+      userId: "u1",
+      episodeId: "e1",
+      redFlags: [spo2Flag, feverFlag],
+    });
+    expect(dispatchMock.mock.calls[0][0].messageKey).toBe(
+      "illness.correlation.redFlagFever",
+    );
+  });
+
+  it("de-dupes when a recent ledger row exists for the episode", async () => {
+    findFirstMock.mockResolvedValueOnce({ id: "prior" });
+    await notifyIllnessRedFlag({
+      userId: "u1",
+      episodeId: "e1",
+      redFlags: [feverFlag],
+    });
+    expect(dispatchMock).not.toHaveBeenCalled();
+    expect(createMock).not.toHaveBeenCalled();
+  });
+
+  it("stamps the ledger anchor before dispatching", async () => {
+    await notifyIllnessRedFlag({
+      userId: "u1",
+      episodeId: "e9",
+      redFlags: [feverFlag],
+    });
+    expect(createMock).toHaveBeenCalledTimes(1);
+    expect(createMock.mock.calls[0][0].data.reason).toContain("e9");
+  });
+
+  it("never throws when dispatch fails", async () => {
+    dispatchMock.mockRejectedValueOnce(new Error("boom"));
+    await expect(
+      notifyIllnessRedFlag({
+        userId: "u1",
+        episodeId: "e1",
+        redFlags: [feverFlag],
+      }),
+    ).resolves.toBeUndefined();
+  });
+});
diff --git a/src/lib/illness/red-flag-notify.ts b/src/lib/illness/red-flag-notify.ts
new file mode 100644
index 000000000..d5cbf8916
--- /dev/null
+++ b/src/lib/illness/red-flag-notify.ts
@@ -0,0 +1,94 @@
+/**
+ * v1.18.4 — illness red-flag escalation push.
+ *
+ * The illness correlation engine (`computeIllnessCorrelation`) surfaces a
+ * retrospective "seek care" red flag when a vital held an absolute clinical
+ * floor for a sustained run (sustained low SpO2, sustained fever). Until now
+ * that escalation only rendered in-app on the correlation surface; it never
+ * left a push. This helper bridges it to the notification dispatcher so the
+ * escalation reaches the user wherever they configured a channel.
+ *
+ * It dispatches at the URGENT level: every configured channel delivers at its
+ * highest urgency (APNs time-sensitive, ntfy max, Web Push `Urgency: high`,
+ * webhook `urgent`). There is NO dependency on APNs — an instance with only
+ * ntfy / Web Push / Telegram / webhook / email still gets the escalation at
+ * the strongest tier those channels support.
+ *
+ * Owner-scoped (the authenticated episode owner) and module-gated by the
+ * caller (`requireIllnessEnabled`). De-duplicated through the `pushAttempt`
+ * ledger: at most one escalation per episode per rolling window, so a
+ * correlation surface that is re-read repeatedly never re-fires the alarm.
+ */
+import { prisma } from "@/lib/db";
+import { getEvent } from "@/lib/logging/context";
+import { dispatchLocalisedNotification } from "@/lib/notifications/dispatch-localised";
+import type { IllnessRedFlag } from "@/lib/illness/correlation";
+
+/** One escalation per episode per this window. */
+const DEDUPE_WINDOW_MS = 24 * 60 * 60 * 1000;
+
+/** Stable ledger reason prefix so the dedupe lookup is exact-matchable. */
+const LEDGER_REASON_PREFIX = "illness_red_flag:";
+
+/**
+ * Emit an urgent escalation push for an episode's red flags, at most once
+ * per `DEDUPE_WINDOW_MS`. No-op when `redFlags` is empty. Never throws —
+ * a notification failure must not break the correlation read.
+ */
+export async function notifyIllnessRedFlag(input: {
+  userId: string;
+  episodeId: string;
+  redFlags: IllnessRedFlag[];
+}): Promise<void> {
+  const { userId, episodeId, redFlags } = input;
+  if (redFlags.length === 0) return;
+
+  try {
+    // Dedupe: skip when an escalation for THIS episode already landed in the
+    // ledger within the window. The episode id rides the `reason` column so
+    // the lookup is exact without a schema change.
+    const reason = `${LEDGER_REASON_PREFIX}${episodeId}`;
+    const since = new Date(Date.now() - DEDUPE_WINDOW_MS);
+    const prior = await prisma.pushAttempt.findFirst({
+      where: { userId, reason, createdAt: { gte: since } },
+      select: { id: true },
+    });
+    if (prior) return;
+
+    // Prefer the most clinically actionable reason for the body. Both copy
+    // keys already exist in every locale bundle (i18n integrity guarantee).
+    const fever = redFlags.find((f) => f.reason === "sustained_fever");
+    const messageKey = fever
+      ? "illness.correlation.redFlagFever"
+      : "illness.correlation.redFlagSpo2";
+
+    // Stamp the ledger BEFORE dispatching so a slow/duplicate concurrent read
+    // can't double-fire. The senders write their own per-channel rows too;
+    // this synthetic row is purely the dedupe anchor.
+    await prisma.pushAttempt.create({
+      data: {
+        userId,
+        channel: "WEB_PUSH",
+        eventType: "SYSTEM_ALERT",
+        result: "skipped",
+        reason,
+      },
+    });
+
+    await dispatchLocalisedNotification({
+      userId,
+      titleKey: "illness.correlation.redFlagTitle",
+      messageKey,
+      eventType: "SYSTEM_ALERT",
+      urgent: true,
+    });
+
+    getEvent()?.addMeta("illness_red_flag_notified", episodeId);
+  } catch (err) {
+    getEvent()?.addWarning(
+      `illness red-flag notify failed for episode ${episodeId}: ${
+        err instanceof Error ? err.message : String(err)
+      }`,
+    );
+  }
+}
diff --git a/src/lib/notifications/dispatch-localised.ts b/src/lib/notifications/dispatch-localised.ts
index 5d20d5f39..e633a91d0 100644
--- a/src/lib/notifications/dispatch-localised.ts
+++ b/src/lib/notifications/dispatch-localised.ts
@@ -59,6 +59,13 @@ interface DispatchLocalisedOptions {
   eventType?: EventType;
   /** Channel-specific extras forwarded to the dispatcher metadata. */
   metadata?: Record<string, unknown>;
+  /**
+   * Escalate to every channel's highest urgency (v1.18.4). Forwarded to
+   * the dispatcher so APNs goes time-sensitive, ntfy max, Web Push
+   * `Urgency: high`, webhook `urgent` — APNs-less instances degrade
+   * gracefully to whatever channels are configured.
+   */
+  urgent?: boolean;
 }
 
 function isLocale(value: string | null | undefined): value is Locale {
@@ -163,5 +170,6 @@ export async function dispatchLocalisedNotification(
     title,
     message,
     metadata,
+    urgent: opts.urgent,
   });
 }
diff --git a/src/lib/notifications/senders/__tests__/apns.test.ts b/src/lib/notifications/senders/__tests__/apns.test.ts
index f41fda74d..72b3072ed 100644
--- a/src/lib/notifications/senders/__tests__/apns.test.ts
+++ b/src/lib/notifications/senders/__tests__/apns.test.ts
@@ -630,6 +630,53 @@ describe("sendViaApns — dispatcher fan-out", () => {
     expect(note.priority).toBe(10);
   });
 
+  it("urgent payload sets time-sensitive + priority=10 on a non-medication event", async () => {
+    // v1.18.4 — an explicitly urgent event (e.g. an illness red-flag
+    // escalation) reaches APNs's strongest no-entitlement tier:
+    // time-sensitive + priority 10, regardless of eventType.
+    vi.mocked(prisma.device.findMany).mockResolvedValueOnce([
+      { id: "d1", apnsToken: "tok-a", apnsEnvironment: "sandbox" },
+    ] as never);
+    sendMock.mockResolvedValueOnce({ sent: [{ device: "tok-a" }], failed: [] });
+    await sendViaApns("u-1", {
+      title: "Seek care",
+      message: "Sustained fever",
+      eventType: "SYSTEM_ALERT",
+      urgent: true,
+    });
+    const note = sendMock.mock.calls[0][0];
+    expect(note.interruptionLevel).toBe("time-sensitive");
+    expect(note.priority).toBe(10);
+  });
+
+  it("urgent payload escalates to critical ONLY with the entitlement env set", async () => {
+    // v1.18.4 — the `critical` level ignores DND/Focus but needs an
+    // Apple-approved entitlement; gate it behind APNS_CRITICAL_ENTITLEMENT.
+    const prev = process.env.APNS_CRITICAL_ENTITLEMENT;
+    process.env.APNS_CRITICAL_ENTITLEMENT = "true";
+    try {
+      vi.mocked(prisma.device.findMany).mockResolvedValueOnce([
+        { id: "d1", apnsToken: "tok-a", apnsEnvironment: "sandbox" },
+      ] as never);
+      sendMock.mockResolvedValueOnce({
+        sent: [{ device: "tok-a" }],
+        failed: [],
+      });
+      await sendViaApns("u-1", {
+        title: "Seek care",
+        message: "Sustained fever",
+        eventType: "SYSTEM_ALERT",
+        urgent: true,
+      });
+      const note = sendMock.mock.calls[0][0];
+      expect(note.interruptionLevel).toBe("critical");
+      expect(note.priority).toBe(10);
+    } finally {
+      if (prev === undefined) delete process.env.APNS_CRITICAL_ENTITLEMENT;
+      else process.env.APNS_CRITICAL_ENTITLEMENT = prev;
+    }
+  });
+
   it.each([
     "MOOD_REMINDER",
     "MEASUREMENT_ANOMALY",
diff --git a/src/lib/notifications/senders/__tests__/urgency.test.ts b/src/lib/notifications/senders/__tests__/urgency.test.ts
new file mode 100644
index 000000000..5edb185ec
--- /dev/null
+++ b/src/lib/notifications/senders/__tests__/urgency.test.ts
@@ -0,0 +1,203 @@
+/**
+ * v1.18.4 — per-channel urgency mapping.
+ *
+ * An urgent payload must reach EACH configured channel at its highest level,
+ * with NO dependency on APNs (most self-hosters have no Apple Developer
+ * account). These tests pin the mapping per sender and confirm an APNs-less
+ * instance degrades gracefully (ntfy / Web Push / webhook still escalate).
+ */
+import { afterEach, beforeEach, describe, expect, it, vi } from "vitest";
+
+const {
+  safeFetchMock,
+  recordPushAttemptMock,
+  sendNotificationMock,
+  findManyMock,
+} = vi.hoisted(() => ({
+  safeFetchMock: vi.fn(),
+  recordPushAttemptMock: vi.fn(),
+  sendNotificationMock: vi.fn(),
+  findManyMock: vi.fn(),
+}));
+
+vi.mock("@/lib/safe-fetch", () => ({
+  safeFetch: (...args: unknown[]) => safeFetchMock(...args),
+  SafeFetchError: class SafeFetchError extends Error {},
+}));
+
+vi.mock("@/lib/logging/context", () => ({
+  getEvent: () => ({
+    addWarning: vi.fn(),
+    addExternalCall: vi.fn(),
+    setError: vi.fn(),
+  }),
+}));
+
+vi.mock("@/lib/notifications/senders/push-attempt-record", () => ({
+  recordPushAttempt: (...args: unknown[]) => recordPushAttemptMock(...args),
+}));
+
+vi.mock("@/lib/db", () => ({
+  prisma: { pushSubscription: { findMany: findManyMock, deleteMany: vi.fn() } },
+}));
+
+vi.mock("@/lib/crypto", () => ({
+  decrypt: (v: string) => v,
+  encrypt: (v: string) => v,
+}));
+
+vi.mock("@/lib/notifications/vapid-config", () => ({
+  getVapidConfig: () =>
+    Promise.resolve({
+      subject: "mailto:a@b.c",
+      publicKey: "pub",
+      privateKey: "priv",
+    }),
+}));
+
+vi.mock("@/lib/validations/notifications", () => ({
+  isPublicUrl: () => true,
+}));
+
+vi.mock("web-push", () => ({
+  setVapidDetails: vi.fn(),
+  sendNotification: (...args: unknown[]) => sendNotificationMock(...args),
+}));
+
+import { sendViaNtfy } from "../ntfy";
+import { sendViaWebhook } from "../webhook";
+import { sendViaWebPush } from "../web-push";
+
+function payload(over?: Record<string, unknown>) {
+  return {
+    eventType: "SYSTEM_ALERT" as const,
+    userId: "user-1",
+    title: "Seek care",
+    message: "Sustained fever",
+    ...over,
+  };
+}
+
+beforeEach(() => {
+  safeFetchMock.mockReset();
+  recordPushAttemptMock.mockReset();
+  sendNotificationMock.mockReset();
+  findManyMock.mockReset();
+});
+
+afterEach(() => vi.clearAllMocks());
+
+describe("ntfy urgent mapping", () => {
+  it("urgent → Priority 5 (max) + warning tag", async () => {
+    safeFetchMock.mockResolvedValue({ ok: true, status: 200 });
+    await sendViaNtfy(
+      { serverUrl: "https://ntfy.example.com", topic: "t" },
+      payload({ urgent: true }),
+    );
+    const [, init] = safeFetchMock.mock.calls[0];
+    const headers = (init as { headers: Record<string, string> }).headers;
+    expect(headers.Priority).toBe("5");
+    expect(headers.Tags).toContain("warning");
+  });
+
+  it("non-urgent SYSTEM_ALERT → default priority, no warning tag", async () => {
+    safeFetchMock.mockResolvedValue({ ok: true, status: 200 });
+    await sendViaNtfy(
+      { serverUrl: "https://ntfy.example.com", topic: "t" },
+      payload(),
+    );
+    const headers = (safeFetchMock.mock.calls[0][1] as {
+      headers: Record<string, string>;
+    }).headers;
+    expect(headers.Priority).toBe("default");
+    expect(headers.Tags).not.toContain("warning");
+  });
+
+  it("discreet urgent keeps the generic tag (no warning leak)", async () => {
+    safeFetchMock.mockResolvedValue({ ok: true, status: 200 });
+    await sendViaNtfy(
+      { serverUrl: "https://ntfy.example.com", topic: "t" },
+      payload({ urgent: true, discreet: true }),
+    );
+    const headers = (safeFetchMock.mock.calls[0][1] as {
+      headers: Record<string, string>;
+    }).headers;
+    expect(headers.Priority).toBe("5");
+    expect(headers.Tags).toBe("reminder");
+  });
+});
+
+describe("webhook urgent mapping", () => {
+  it("urgent → priority 'urgent' in the JSON body", async () => {
+    safeFetchMock.mockResolvedValue({ ok: true, status: 200 });
+    await sendViaWebhook(
+      { url: "https://relay.example.com" },
+      payload({ urgent: true }),
+    );
+    const body = JSON.parse(
+      (safeFetchMock.mock.calls[0][1] as { body: string }).body,
+    );
+    expect(body.priority).toBe("urgent");
+  });
+
+  it("non-urgent → priority 'default'", async () => {
+    safeFetchMock.mockResolvedValue({ ok: true, status: 200 });
+    await sendViaWebhook({ url: "https://relay.example.com" }, payload());
+    const body = JSON.parse(
+      (safeFetchMock.mock.calls[0][1] as { body: string }).body,
+    );
+    expect(body.priority).toBe("default");
+  });
+});
+
+describe("web-push urgent mapping", () => {
+  it("urgent → Urgency:high option + requireInteraction in payload", async () => {
+    findManyMock.mockResolvedValue([
+      { id: "s1", endpoint: "https://push.example.com/x", p256dh: "a", auth: "b" },
+    ]);
+    sendNotificationMock.mockResolvedValue(undefined);
+    await sendViaWebPush("user-1", payload({ urgent: true }));
+    const [, body, options] = sendNotificationMock.mock.calls[0];
+    expect((options as { urgency?: string }).urgency).toBe("high");
+    expect(JSON.parse(body as string).requireInteraction).toBe(true);
+  });
+
+  it("non-urgent → no urgency option, requireInteraction false", async () => {
+    findManyMock.mockResolvedValue([
+      { id: "s1", endpoint: "https://push.example.com/x", p256dh: "a", auth: "b" },
+    ]);
+    sendNotificationMock.mockResolvedValue(undefined);
+    await sendViaWebPush("user-1", payload());
+    const [, body, options] = sendNotificationMock.mock.calls[0];
+    expect(options).toBeUndefined();
+    expect(JSON.parse(body as string).requireInteraction).toBe(false);
+  });
+});
+
+describe("APNs-less instance degrades gracefully", () => {
+  it("an urgent event still escalates ntfy + Web Push with no APNs configured", async () => {
+    // No APNs env, no APNs channel — the urgent event reaches the channels
+    // that ARE present at their top tier.
+    safeFetchMock.mockResolvedValue({ ok: true, status: 200 });
+    findManyMock.mockResolvedValue([
+      { id: "s1", endpoint: "https://push.example.com/x", p256dh: "a", auth: "b" },
+    ]);
+    sendNotificationMock.mockResolvedValue(undefined);
+
+    const ntfy = await sendViaNtfy(
+      { serverUrl: "https://ntfy.example.com", topic: "t" },
+      payload({ urgent: true }),
+    );
+    const web = await sendViaWebPush("user-1", payload({ urgent: true }));
+
+    expect(ntfy.ok).toBe(true);
+    expect(web.ok).toBe(true);
+    expect(
+      (safeFetchMock.mock.calls[0][1] as { headers: Record<string, string> })
+        .headers.Priority,
+    ).toBe("5");
+    expect(
+      (sendNotificationMock.mock.calls[0][2] as { urgency?: string }).urgency,
+    ).toBe("high");
+  });
+});
diff --git a/src/lib/notifications/senders/apns.ts b/src/lib/notifications/senders/apns.ts
index 511989863..1e50797b9 100644
--- a/src/lib/notifications/senders/apns.ts
+++ b/src/lib/notifications/senders/apns.ts
@@ -525,6 +525,7 @@ export async function sendViaApns(
     eventType: string;
     metadata?: Record<string, unknown>;
     discreet?: boolean;
+    urgent?: boolean;
   },
 ): Promise<SendOutcome> {
   const config = loadApnsConfig();
@@ -595,13 +596,28 @@ export async function sendViaApns(
         ? (["production", "sandbox"] as const)
         : (["sandbox", "production"] as const);
 
-    // SB-5 v1.4.40 — only MEDICATION_REMINDER opts in to Focus-bypass.
-    // The user explicitly asked the server to nudge them about a dose;
-    // a missed dose is the textbook "time-sensitive" use case Apple
+    // SB-5 v1.4.40 — only MEDICATION_REMINDER opts in to Focus-bypass by
+    // default. The user explicitly asked the server to nudge them about a
+    // dose; a missed dose is the textbook "time-sensitive" use case Apple
     // sanctions. Every other event-type (mood nudges, anomaly alerts,
-    // PRs, system messages) must stay on the default `active` level so
-    // Focus modes — including Sleep — silence them as the user expects.
-    const isTimeSensitive = payload.eventType === "MEDICATION_REMINDER";
+    // PRs, system messages) stays on the default `active` level so Focus
+    // modes — including Sleep — silence them as the user expects.
+    //
+    // v1.18.4 — an explicitly urgent payload (e.g. an illness red-flag
+    // "seek care" escalation) ALSO opts in to time-sensitive: it is the
+    // strongest level the APNs sender can reach without an Apple-approved
+    // entitlement, and the channel-agnostic urgency model wants every
+    // channel at its highest tier for an urgent event.
+    const isTimeSensitive =
+      payload.eventType === "MEDICATION_REMINDER" || payload.urgent === true;
+    // The `critical` interruption-level ignores DND/Focus completely but
+    // is gated behind an Apple-approved entitlement (`com.apple.developer.
+    // usernotifications.critical-alerts`). Only emit it when the operator
+    // has confirmed the build carries the entitlement — otherwise APNs
+    // rejects the push. Default off; time-sensitive is the safe floor.
+    const useCritical =
+      payload.urgent === true &&
+      process.env.APNS_CRITICAL_ENTITLEMENT === "true";
 
     let result: Awaited<ReturnType<typeof sendApnsPush>> | null = null;
     // Discreet mode (cycle privacy): the lock-screen-visible routing
@@ -645,7 +661,9 @@ export async function sendViaApns(
           mutableContent: true,
           ...(isTimeSensitive
             ? {
-                interruptionLevel: "time-sensitive" as const,
+                interruptionLevel: useCritical
+                  ? ("critical" as const)
+                  : ("time-sensitive" as const),
                 priority: 10 as const,
               }
             : {}),
diff --git a/src/lib/notifications/senders/ntfy.ts b/src/lib/notifications/senders/ntfy.ts
index 7878c8c92..7a673f974 100644
--- a/src/lib/notifications/senders/ntfy.ts
+++ b/src/lib/notifications/senders/ntfy.ts
@@ -8,6 +8,7 @@ import { getEvent } from "@/lib/logging/context";
 import { recordPushAttempt } from "@/lib/notifications/senders/push-attempt-record";
 import { safeFetch } from "@/lib/safe-fetch";
 import { plainPushText } from "@/lib/notifications/strip-emoji";
+import { isUrgentPayload } from "@/lib/notifications/types";
 
 /**
  * Send notification via ntfy (simple HTTP POST).
@@ -26,16 +27,28 @@ export async function sendViaNtfy(
   try {
     const url = `${config.serverUrl.replace(/\/$/, "")}/${encodeURIComponent(config.topic)}`;
 
+    // v1.18.4 — an explicitly urgent payload escalates to ntfy's top
+    // priority (`5` / max) so it bypasses the relay's batching and surfaces
+    // loudest; MEDICATION_REMINDER keeps its long-standing `high` (4); the
+    // rest stay `default` (3). `urgent` also adds a tag so the lock-screen
+    // entry reads as an alert (unless discreet privacy collapses tags).
+    const urgent = isUrgentPayload(payload) && payload.urgent === true;
+    const priority = urgent
+      ? "5"
+      : payload.eventType === "MEDICATION_REMINDER"
+        ? "high"
+        : "default";
+    const eventTag = payload.discreet
+      ? "reminder"
+      : payload.eventType.toLowerCase().replace(/_/g, "-");
     const headers: Record<string, string> = {
       Title: plainPushText(payload.title, payload.eventType),
-      Priority:
-        payload.eventType === "MEDICATION_REMINDER" ? "high" : "default",
+      Priority: priority,
       // Discreet mode (cycle privacy): the X-Tags header is visible on the
       // lock screen, so collapse it to a generic tag instead of leaking the
-      // cycle event name.
-      Tags: payload.discreet
-        ? "reminder"
-        : payload.eventType.toLowerCase().replace(/_/g, "-"),
+      // cycle event name. An urgent (non-discreet) event also carries a
+      // `warning` tag so the entry renders as an alert.
+      Tags: urgent && !payload.discreet ? `warning,${eventTag}` : eventTag,
     };
 
     if (config.authToken) {
diff --git a/src/lib/notifications/senders/web-push.ts b/src/lib/notifications/senders/web-push.ts
index 2ff484147..0d4900d47 100644
--- a/src/lib/notifications/senders/web-push.ts
+++ b/src/lib/notifications/senders/web-push.ts
@@ -99,8 +99,19 @@ export async function sendViaWebPush(
         payload.metadata.url.startsWith("/")
           ? payload.metadata.url
           : "/",
+      // v1.18.4 — urgent events ask the service worker to keep the
+      // notification on screen until the user acts on it (where the
+      // browser honours `requireInteraction`).
+      requireInteraction: payload.urgent === true,
     });
 
+    // v1.18.4 — the Web Push `Urgency` header (RFC 8030) tells the push
+    // service to deliver immediately rather than batching for power. An
+    // urgent event uses `high`; everything else keeps the library default.
+    const sendOptions = payload.urgent === true
+      ? ({ urgency: "high" as const } as const)
+      : undefined;
+
     let anySuccess = false;
     const expiredIds: string[] = [];
     let lastTransientStatus: number | undefined;
@@ -128,6 +139,7 @@ export async function sendViaWebPush(
             keys: { p256dh, auth },
           },
           pushPayload,
+          sendOptions,
         );
         anySuccess = true;
         allPermanentReject = false;
diff --git a/src/lib/notifications/senders/webhook.ts b/src/lib/notifications/senders/webhook.ts
index 68add9be9..e7a890aee 100644
--- a/src/lib/notifications/senders/webhook.ts
+++ b/src/lib/notifications/senders/webhook.ts
@@ -53,8 +53,15 @@ export async function sendViaWebhook(
         payload.eventType,
       ),
       eventType: payload.discreet ? "reminder" : payload.eventType,
+      // v1.18.4 — an explicitly urgent event maps to `urgent` so a relay
+      // rule (Gotify priority, Discord mention, Home Assistant automation)
+      // can escalate; MEDICATION_REMINDER keeps `high`; the rest `default`.
       priority:
-        payload.eventType === "MEDICATION_REMINDER" ? "high" : "default",
+        payload.urgent === true
+          ? "urgent"
+          : payload.eventType === "MEDICATION_REMINDER"
+            ? "high"
+            : "default",
     });
 
     const res = await safeFetch(
diff --git a/src/lib/notifications/types.ts b/src/lib/notifications/types.ts
index ea23e1ce9..b338b566c 100644
--- a/src/lib/notifications/types.ts
+++ b/src/lib/notifications/types.ts
@@ -219,4 +219,33 @@ export interface NotificationPayload {
    * — the title/body are already masked upstream.
    */
   discreet?: boolean;
+  /**
+   * Urgent / escalation dimension (v1.18.4). When true, EVERY configured
+   * channel delivers at the HIGHEST urgency it supports — never assuming
+   * APNs is one of them (most self-hosters have no Apple Developer account):
+   *  - APNs    → interruption-level `time-sensitive` + priority 10 (and
+   *    `critical` only when `APNS_CRITICAL_ENTITLEMENT=true`, since the
+   *    critical flag needs an Apple-approved entitlement; time-sensitive
+   *    does not).
+   *  - ntfy    → `Priority: 5` (max) + an `urgent` tag.
+   *  - WebPush → `Urgency: high` header + `requireInteraction`.
+   *  - Webhook → `priority: "urgent"` in the JSON body.
+   *  - Telegram → normal delivery (no urgency tier exists; never silent).
+   * Normal events leave `urgent` unset and behave exactly as before.
+   */
+  urgent?: boolean;
+}
+
+/**
+ * Whether a payload should escalate to each channel's highest urgency.
+ * Explicit `urgent: true` is the modern signal. `MEDICATION_REMINDER`
+ * stays escalated for backward compatibility (it has shipped as APNs
+ * time-sensitive / ntfy high since v1.4.40), so callers that don't set
+ * the flag keep their existing behaviour.
+ */
+export function isUrgentPayload(payload: {
+  urgent?: boolean;
+  eventType: string;
+}): boolean {
+  return payload.urgent === true || payload.eventType === "MEDICATION_REMINDER";
 }