feat(medications): Wirkung tab + Insights efficacy summary

Add the per-medication "Wirkung" tab (hidden for one-shot and no-target meds)
rendering the target series with a start marker, dose-change markers, shaded
pause bands and a faint reference band, an adherence lane, a neutral
before/after-start card with honest empty states, an optional level-shift note,
and a retarget chooser. Weave a compact, read-only efficacy summary into the
Insights medication surface that reads the same DTO and links through to the
tab. All copy is descriptive; add a banned-verdict-verb guard test over the
medications.efficacy namespace across all six locales.

messages/de.json

@@ -1593,7 +1593,8 @@
         "verlauf": "Verlauf",
         "injektion": "Injektion",
         "api": "API",
-        "erweitert": "Erweitert"
+        "erweitert": "Erweitert",
+        "wirkung": "Wirkung"
       },
       "shell": {
         "loadFailed": "Dieses Medikament konnte nicht geladen werden.",
@@ -1791,7 +1792,41 @@
     "reorderDescription": "Bestimme die Reihenfolge deiner Medikamente – sie gilt für die Karten- und die Tabellenansicht.",
     "reorderSaved": "Reihenfolge gespeichert",
     "reorderSaveFailed": "Reihenfolge konnte nicht gespeichert werden",
-    "customize": "Medikamente anpassen"
+    "customize": "Medikamente anpassen",
+    "efficacy": {
+      "title": "Wirkung",
+      "intro": "Wie sich die Messwerte, die dieses Medikament beeinflussen soll, rund um den Beginn der Einnahme entwickelt haben. Es zeigt den zeitlichen Zusammenhang – eine Assoziation, keine Ursache – und keine Empfehlung zu Behandlung oder Dosis.",
+      "notEligible": "Für dieses Medikament gibt es keinen zugehörigen Messwert.",
+      "startFallback": "Es ist kein Startdatum hinterlegt, daher dient der erste erfasste Wert als Bezugspunkt.",
+      "noStart": "Hinterlege ein Startdatum, um die Werte vor und nach Beginn zu vergleichen.",
+      "disclaimer": "Nur ein Zusammenhang: Die Zahlen zeigen, was sich im selben Zeitraum verändert hat, nicht dass das Medikament die Veränderung verursacht hat. Besprich Entscheidungen zu deiner Behandlung mit deiner Ärztin oder deinem Arzt.",
+      "primaryBadge": "Hauptziel",
+      "noSeries": "Für diesen Zielwert sind noch keine Messungen erfasst.",
+      "startMarker": "Beginn",
+      "adherenceLane": "Einnahmetreue",
+      "typicalRange": "Üblicher Bereich",
+      "levelShift": "Um {date} wurde eine Verschiebung des Niveaus erkannt.",
+      "retarget": {
+        "label": "Nicht der richtige Messwert?",
+        "placeholder": "Verfolgen anhand…",
+        "apply": "Übernehmen",
+        "reset": "Auf Standard zurücksetzen"
+      },
+      "beforeAfter": {
+        "summary": "Ø {before} davor → Ø {after} seitdem – eine Veränderung von {delta}.",
+        "counts": "Basierend auf {beforeCount} Werten davor und {afterCount} seitdem.",
+        "needBefore": "Noch zu wenige Werte vor dem Beginn – für einen Vergleich werden etwa {weeks} Wochen davor und danach benötigt.",
+        "needAfter": "Noch zu wenige Werte seit dem Beginn – für einen Vergleich werden etwa {weeks} Wochen davor und danach benötigt.",
+        "needStart": "Hinterlege ein Startdatum, um die Werte vor und nach Beginn zu vergleichen.",
+        "needData": "Noch zu wenige Werte – für einen Vergleich werden etwa {weeks} Wochen vor und nach dem Beginn benötigt."
+      },
+      "insights": {
+        "title": "Medikamenten-Wirkung",
+        "subtitle": "Was mit den Zielwerten deiner Medikamente zeitlich zusammenfällt – nur ein Zusammenhang, kein Urteil.",
+        "link": "Wirkung öffnen",
+        "empty": "Noch nicht genug Daten, um deine Medikamente mit ihren Zielwerten in Beziehung zu setzen."
+      }
+    }
   },
   "charts": {
     "loadingLabel": "Diagramm wird geladen…",

messages/en.json

@@ -1593,7 +1593,8 @@
         "verlauf": "History",
         "injektion": "Injection",
         "api": "API",
-        "erweitert": "Advanced"
+        "erweitert": "Advanced",
+        "wirkung": "Effect"
       },
       "shell": {
         "loadFailed": "This medication could not be loaded.",
@@ -1791,7 +1792,41 @@
     "reorderDescription": "Set the order of your medications – it applies to both the card and the table view.",
     "reorderSaved": "Order saved",
     "reorderSaveFailed": "Order could not be saved",
-    "customize": "Customize medications"
+    "customize": "Customize medications",
+    "efficacy": {
+      "title": "Effect",
+      "intro": "How the measurements this medication is meant to influence have moved around the time you started it. It shows what lines up in time — an association, not a cause — and never advice about your treatment or dose.",
+      "notEligible": "There is no outcome to relate this medication to.",
+      "startFallback": "No start date is set, so the comparison uses your first recorded reading as the reference point.",
+      "noStart": "Set a start date for this medication to compare the readings before and after it began.",
+      "disclaimer": "Association only: these figures show what changed over the same period, not that the medication caused the change. Discuss any decision about your treatment with your doctor.",
+      "primaryBadge": "Main target",
+      "noSeries": "No readings recorded for this target yet.",
+      "startMarker": "Start",
+      "adherenceLane": "Adherence",
+      "typicalRange": "Typical range",
+      "levelShift": "A shift in the level was detected around {date}.",
+      "retarget": {
+        "label": "Not the right measurement?",
+        "placeholder": "Track against…",
+        "apply": "Apply",
+        "reset": "Reset to default"
+      },
+      "beforeAfter": {
+        "summary": "Ø {before} before → Ø {after} since — a change of {delta}.",
+        "counts": "Based on {beforeCount} readings before and {afterCount} since.",
+        "needBefore": "Not enough readings before the start yet — about {weeks} weeks are needed before and after to compare.",
+        "needAfter": "Not enough readings since the start yet — about {weeks} weeks are needed before and after to compare.",
+        "needStart": "Set a start date to compare the readings before and after it began.",
+        "needData": "Not enough readings yet — about {weeks} weeks are needed before and after the start to compare."
+      },
+      "insights": {
+        "title": "Medication effect",
+        "subtitle": "What lines up with the measurements your medications target — association only, never a verdict.",
+        "link": "Open the effect view",
+        "empty": "Not enough data yet to relate your medications to their target measurements."
+      }
+    }
   },
   "charts": {
     "loadingLabel": "Loading chart…",

messages/es.json

@@ -1593,7 +1593,8 @@
         "verlauf": "Historial",
         "injektion": "Inyección",
         "api": "API",
-        "erweitert": "Avanzado"
+        "erweitert": "Avanzado",
+        "wirkung": "Efecto"
       },
       "shell": {
         "loadFailed": "No se pudo cargar este medicamento.",
@@ -1791,7 +1792,41 @@
     "reorderDescription": "Define el orden de tus medicamentos: se aplica a la vista de tarjetas y a la de tabla.",
     "reorderSaved": "Orden guardado",
     "reorderSaveFailed": "No se pudo guardar el orden",
-    "customize": "Personalizar medicamentos"
+    "customize": "Personalizar medicamentos",
+    "efficacy": {
+      "title": "Efecto",
+      "intro": "Cómo han evolucionado las mediciones sobre las que actúa este medicamento en torno al momento en que empezaste a tomarlo. Muestra lo que coincide en el tiempo: una asociación, no una causa, y nunca un consejo sobre tu tratamiento o dosis.",
+      "notEligible": "No hay ninguna medición que relacionar con este medicamento.",
+      "startFallback": "No hay fecha de inicio, así que la comparación usa tu primera lectura registrada como referencia.",
+      "noStart": "Añade una fecha de inicio para comparar las lecturas antes y después de empezar.",
+      "disclaimer": "Solo asociación: estas cifras muestran lo que cambió en el mismo periodo, no que el medicamento causara el cambio. Consulta cualquier decisión sobre tu tratamiento con tu médico.",
+      "primaryBadge": "Objetivo principal",
+      "noSeries": "Aún no hay mediciones registradas para este objetivo.",
+      "startMarker": "Inicio",
+      "adherenceLane": "Adherencia",
+      "typicalRange": "Rango habitual",
+      "levelShift": "Se detectó un cambio de nivel en torno a {date}.",
+      "retarget": {
+        "label": "¿No es la medición correcta?",
+        "placeholder": "Seguir según…",
+        "apply": "Aplicar",
+        "reset": "Restablecer al valor predeterminado"
+      },
+      "beforeAfter": {
+        "summary": "Ø {before} antes → Ø {after} desde entonces: un cambio de {delta}.",
+        "counts": "Basado en {beforeCount} lecturas antes y {afterCount} desde entonces.",
+        "needBefore": "Aún no hay suficientes lecturas antes del inicio: se necesitan unas {weeks} semanas antes y después para comparar.",
+        "needAfter": "Aún no hay suficientes lecturas desde el inicio: se necesitan unas {weeks} semanas antes y después para comparar.",
+        "needStart": "Añade una fecha de inicio para comparar las lecturas antes y después de empezar.",
+        "needData": "Aún no hay suficientes lecturas: se necesitan unas {weeks} semanas antes y después del inicio para comparar."
+      },
+      "insights": {
+        "title": "Efecto de la medicación",
+        "subtitle": "Lo que coincide con las mediciones que persiguen tus medicamentos: solo asociación, nunca un veredicto.",
+        "link": "Abrir la vista de efecto",
+        "empty": "Aún no hay suficientes datos para relacionar tus medicamentos con sus mediciones objetivo."
+      }
+    }
   },
   "charts": {
     "loadingLabel": "Cargando la gráfica…",

messages/fr.json

@@ -1593,7 +1593,8 @@
         "verlauf": "Historique",
         "injektion": "Injection",
         "api": "API",
-        "erweitert": "Avancé"
+        "erweitert": "Avancé",
+        "wirkung": "Effet"
       },
       "shell": {
         "loadFailed": "Ce médicament n'a pas pu être chargé.",
@@ -1791,7 +1792,41 @@
     "reorderDescription": "Définis l'ordre de tes médicaments – il s'applique à la vue cartes et à la vue tableau.",
     "reorderSaved": "Ordre enregistré",
     "reorderSaveFailed": "L'ordre n'a pas pu être enregistré",
-    "customize": "Personnaliser les médicaments"
+    "customize": "Personnaliser les médicaments",
+    "efficacy": {
+      "title": "Effet",
+      "intro": "Comment les mesures que ce médicament vise ont évolué autour du moment où vous avez commencé à le prendre. Cela montre ce qui coïncide dans le temps : une association, pas une cause, et jamais un conseil sur votre traitement ou votre dose.",
+      "notEligible": "Aucune mesure à relier à ce médicament.",
+      "startFallback": "Aucune date de début n'est renseignée ; la comparaison utilise donc votre première mesure enregistrée comme référence.",
+      "noStart": "Renseignez une date de début pour comparer les mesures avant et après le début.",
+      "disclaimer": "Association seulement : ces chiffres montrent ce qui a changé sur la même période, pas que le médicament a causé ce changement. Discutez de toute décision concernant votre traitement avec votre médecin.",
+      "primaryBadge": "Cible principale",
+      "noSeries": "Aucune mesure enregistrée pour cette cible pour le moment.",
+      "startMarker": "Début",
+      "adherenceLane": "Observance",
+      "typicalRange": "Plage habituelle",
+      "levelShift": "Un changement de niveau a été détecté autour du {date}.",
+      "retarget": {
+        "label": "Ce n'est pas la bonne mesure ?",
+        "placeholder": "Suivre selon…",
+        "apply": "Appliquer",
+        "reset": "Réinitialiser par défaut"
+      },
+      "beforeAfter": {
+        "summary": "Ø {before} avant → Ø {after} depuis — un écart de {delta}.",
+        "counts": "D'après {beforeCount} mesures avant et {afterCount} depuis.",
+        "needBefore": "Pas encore assez de mesures avant le début — il faut environ {weeks} semaines avant et après pour comparer.",
+        "needAfter": "Pas encore assez de mesures depuis le début — il faut environ {weeks} semaines avant et après pour comparer.",
+        "needStart": "Renseignez une date de début pour comparer les mesures avant et après le début.",
+        "needData": "Pas encore assez de mesures — il faut environ {weeks} semaines avant et après le début pour comparer."
+      },
+      "insights": {
+        "title": "Effet des médicaments",
+        "subtitle": "Ce qui coïncide avec les mesures visées par vos médicaments — association seulement, jamais un verdict.",
+        "link": "Ouvrir la vue Effet",
+        "empty": "Pas encore assez de données pour relier vos médicaments à leurs mesures cibles."
+      }
+    }
   },
   "charts": {
     "loadingLabel": "Chargement du graphique…",

messages/it.json

@@ -1593,7 +1593,8 @@
         "verlauf": "Cronologia",
         "injektion": "Iniezione",
         "api": "API",
-        "erweitert": "Avanzate"
+        "erweitert": "Avanzate",
+        "wirkung": "Effetto"
       },
       "shell": {
         "loadFailed": "Impossibile caricare questo farmaco.",
@@ -1791,7 +1792,41 @@
     "reorderDescription": "Imposta l'ordine dei tuoi farmaci: vale per la vista a schede e per la tabella.",
     "reorderSaved": "Ordine salvato",
     "reorderSaveFailed": "Impossibile salvare l’ordine",
-    "customize": "Personalizza i farmaci"
+    "customize": "Personalizza i farmaci",
+    "efficacy": {
+      "title": "Effetto",
+      "intro": "Come sono cambiate le misurazioni su cui agisce questo farmaco intorno al momento in cui hai iniziato a prenderlo. Mostra ciò che coincide nel tempo: un'associazione, non una causa, e mai un consiglio sul trattamento o sulla dose.",
+      "notEligible": "Non c'è alcuna misurazione da collegare a questo farmaco.",
+      "startFallback": "Non è impostata una data di inizio, quindi il confronto usa la tua prima misurazione registrata come riferimento.",
+      "noStart": "Imposta una data di inizio per confrontare le misurazioni prima e dopo l'avvio.",
+      "disclaimer": "Solo associazione: questi numeri mostrano ciò che è cambiato nello stesso periodo, non che il farmaco abbia causato il cambiamento. Discuti ogni decisione sul tuo trattamento con il medico.",
+      "primaryBadge": "Obiettivo principale",
+      "noSeries": "Nessuna misurazione registrata per questo obiettivo.",
+      "startMarker": "Inizio",
+      "adherenceLane": "Aderenza",
+      "typicalRange": "Intervallo abituale",
+      "levelShift": "È stato rilevato un cambio di livello intorno al {date}.",
+      "retarget": {
+        "label": "Non è la misurazione giusta?",
+        "placeholder": "Monitora in base a…",
+        "apply": "Applica",
+        "reset": "Ripristina predefinito"
+      },
+      "beforeAfter": {
+        "summary": "Ø {before} prima → Ø {after} da allora — una variazione di {delta}.",
+        "counts": "In base a {beforeCount} misurazioni prima e {afterCount} da allora.",
+        "needBefore": "Ancora troppe poche misurazioni prima dell'inizio: servono circa {weeks} settimane prima e dopo per confrontare.",
+        "needAfter": "Ancora troppe poche misurazioni dall'inizio: servono circa {weeks} settimane prima e dopo per confrontare.",
+        "needStart": "Imposta una data di inizio per confrontare le misurazioni prima e dopo l'avvio.",
+        "needData": "Ancora troppe poche misurazioni: servono circa {weeks} settimane prima e dopo l'inizio per confrontare."
+      },
+      "insights": {
+        "title": "Effetto dei farmaci",
+        "subtitle": "Ciò che coincide con le misurazioni a cui mirano i tuoi farmaci: solo associazione, mai un verdetto.",
+        "link": "Apri la vista Effetto",
+        "empty": "Ancora non ci sono dati sufficienti per collegare i tuoi farmaci alle loro misurazioni obiettivo."
+      }
+    }
   },
   "charts": {
     "loadingLabel": "Caricamento del grafico…",

messages/pl.json

@@ -1593,7 +1593,8 @@
         "verlauf": "Historia",
         "injektion": "Iniekcja",
         "api": "API",
-        "erweitert": "Zaawansowane"
+        "erweitert": "Zaawansowane",
+        "wirkung": "Działanie"
       },
       "shell": {
         "loadFailed": "Nie udało się załadować tego leku.",
@@ -1791,7 +1792,41 @@
     "reorderDescription": "Ustal kolejność swoich leków – obowiązuje w widoku kart i w tabeli.",
     "reorderSaved": "Kolejność zapisana",
     "reorderSaveFailed": "Nie udało się zapisać kolejności",
-    "customize": "Dostosuj leki"
+    "customize": "Dostosuj leki",
+    "efficacy": {
+      "title": "Działanie",
+      "intro": "Jak zmieniały się pomiary, na które ma wpływać ten lek, w okolicach rozpoczęcia jego przyjmowania. Pokazuje to, co zbiega się w czasie — powiązanie, nie przyczynę — i nigdy porady dotyczącej leczenia ani dawki.",
+      "notEligible": "Brak pomiaru, który można powiązać z tym lekiem.",
+      "startFallback": "Nie ustawiono daty rozpoczęcia, więc porównanie używa pierwszego zapisanego pomiaru jako punktu odniesienia.",
+      "noStart": "Ustaw datę rozpoczęcia, aby porównać pomiary sprzed i po rozpoczęciu.",
+      "disclaimer": "Tylko powiązanie: te liczby pokazują, co zmieniło się w tym samym okresie, a nie że lek spowodował tę zmianę. Wszelkie decyzje dotyczące leczenia omów z lekarzem.",
+      "primaryBadge": "Główny cel",
+      "noSeries": "Brak zapisanych pomiarów dla tego celu.",
+      "startMarker": "Początek",
+      "adherenceLane": "Regularność",
+      "typicalRange": "Typowy zakres",
+      "levelShift": "Wykryto zmianę poziomu w okolicach {date}.",
+      "retarget": {
+        "label": "To nie ten pomiar?",
+        "placeholder": "Śledź według…",
+        "apply": "Zastosuj",
+        "reset": "Przywróć domyślne"
+      },
+      "beforeAfter": {
+        "summary": "Ø {before} przedtem → Ø {after} od tego czasu — zmiana o {delta}.",
+        "counts": "Na podstawie {beforeCount} pomiarów przedtem i {afterCount} od tego czasu.",
+        "needBefore": "Za mało pomiarów przed rozpoczęciem — do porównania potrzeba około {weeks} tygodni przed i po.",
+        "needAfter": "Za mało pomiarów od rozpoczęcia — do porównania potrzeba około {weeks} tygodni przed i po.",
+        "needStart": "Ustaw datę rozpoczęcia, aby porównać pomiary sprzed i po rozpoczęciu.",
+        "needData": "Za mało pomiarów — do porównania potrzeba około {weeks} tygodni przed i po rozpoczęciu."
+      },
+      "insights": {
+        "title": "Działanie leków",
+        "subtitle": "Co zbiega się w czasie z pomiarami, na które celują Twoje leki — tylko powiązanie, nigdy werdykt.",
+        "link": "Otwórz widok działania",
+        "empty": "Za mało danych, aby powiązać Twoje leki z docelowymi pomiarami."
+      }
+    }
   },
   "charts": {
     "loadingLabel": "Ładowanie wykresu…",

src/__tests__/medications-efficacy-verb-guard.test.ts

@@ -0,0 +1,105 @@
+/**
+ * v1.28 — banned-verb guard for the `medications.efficacy.*` namespace.
+ *
+ * The medication-efficacy view ("Wirkung") is a medication-adjacent claim, so
+ * its safety boundary is structural, not left to reviewer vigilance: the DTO
+ * carries no verdict / score field, and the copy must stay strictly
+ * descriptive — an association, never "the drug works / is effective", never a
+ * dose change. This test walks every efficacy string in all six locales and
+ * fails if any value contains a verdict or dose-advice verb, so a forbidden
+ * word can never creep into the bundle. Mirrors the `i18n-english-leak-guard`
+ * flatten + filter + `toEqual([])` pattern.
+ *
+ * If this fails: rewrite the offending string to descriptive phrasing (numbers
+ * + neutral connectives). Do NOT weaken the denylist to pass.
+ */
+import { readFileSync, readdirSync } from "node:fs";
+import { join } from "node:path";
+import { describe, it, expect } from "vitest";
+
+const MESSAGES = join(__dirname, "..", "..", "messages");
+const LOCALES = readdirSync(MESSAGES).filter((f) => f.endsWith(".json"));
+
+/** Verdict + efficacy-adjective + dose-advice verbs across the six locales. */
+const BANNED: RegExp[] = [
+  // English
+  /\bworks?\b/i,
+  /\bworking\b/i,
+  /\beffective(ly)?\b/i,
+  /\bineffective\b/i,
+  /\bcures?\b/i,
+  /\bcured\b/i,
+  /\bheals?\b/i,
+  /\bhealed\b/i,
+  /\bimprove(d|s|ment)?\b/i,
+  /\bworsen(ed|s)?\b/i,
+  /\bbetter\b/i,
+  /\bworse\b/i,
+  /\bincrease\b/i,
+  /\bdecrease\b/i,
+  /\breduce\b/i,
+  /\braise\b/i,
+  /\bsuccess(ful)?\b/i,
+  // German
+  /\bwirksam\b/i,
+  /\bunwirksam\b/i,
+  /\banschlägt\b/i,
+  /\bheilt\b/i,
+  /\bverbessert\b/i,
+  /\bverschlechtert\b/i,
+  /\berhöhen\b/i,
+  /\bsenken\b/i,
+  /\babsetzen\b/i,
+  // Spanish
+  /\bfunciona\b/i,
+  /\beficaz\b/i,
+  /\bineficaz\b/i,
+  /\bmejora\b/i,
+  /\bempeora\b/i,
+  // French
+  /\befficace\b/i,
+  /\binefficace\b/i,
+  /\baméliore\b/i,
+  /\baggrave\b/i,
+  // Italian
+  /\bmigliora\b/i,
+  /\bpeggiora\b/i,
+  // Polish
+  /\bskuteczn\w*\b/i,
+  /\bpoprawia\b/i,
+  /\bpogarsza\b/i,
+];
+
+function flatten(obj: unknown, prefix: string, out: [string, string][]): void {
+  if (obj === null || typeof obj !== "object") return;
+  for (const [k, v] of Object.entries(obj as Record<string, unknown>)) {
+    const key = prefix ? `${prefix}.${k}` : k;
+    if (typeof v === "string") out.push([key, v]);
+    else flatten(v, key, out);
+  }
+}
+
+describe("medications.efficacy — banned verdict/advice verbs", () => {
+  it.each(LOCALES)("%s carries no forbidden verb", (file) => {
+    const bundle = JSON.parse(readFileSync(join(MESSAGES, file), "utf8")) as {
+      medications?: { efficacy?: unknown };
+    };
+    const efficacy = bundle.medications?.efficacy;
+    expect(efficacy, `${file} is missing medications.efficacy`).toBeDefined();
+
+    const flat: [string, string][] = [];
+    flatten(efficacy, "medications.efficacy", flat);
+    expect(flat.length).toBeGreaterThan(0);
+
+    const violations = flat
+      .filter(([, value]) => BANNED.some((re) => re.test(value)))
+      .map(([key, value]) => `${key} = ${JSON.stringify(value)}`);
+
+    expect(
+      violations,
+      `Forbidden verdict/advice verb in ${file} — the efficacy view is ` +
+        `association-only. Rewrite to descriptive phrasing:\n` +
+        violations.map((v) => `  ${v}`).join("\n"),
+    ).toEqual([]);
+  });
+});

src/app/insights/medications/page.tsx

@@ -17,6 +17,7 @@ import { ComplianceHeatmap } from "@/components/charts/compliance-heatmap";
 import { CoachLaunchButton } from "@/components/insights/coach-launch-button";
 import { InsightStatusCard } from "@/components/insights/insight-status-card";
 import { MetricTargetSummary } from "@/components/insights/metric-target-summary";
+import { MedicationEfficacySummary } from "@/components/insights/medication-efficacy-summary";
 import { SubPageShell } from "@/components/insights/sub-page-shell";
 import { TileHeader } from "@/components/insights/tile-header";
 import { apiGet } from "@/lib/api/api-fetch";
@@ -280,6 +281,13 @@ export default function InsightsMedikamentePage() {
         })}
       </div>
 
+      {/* v1.28 — compact efficacy summary: reuses the same server-computed
+          efficacy DTO the detail-page "Wirkung" tab reads (never a second
+          computation), association-only, linking through to the full view. */}
+      <MedicationEfficacySummary
+        medications={medications.map((m) => ({ id: m.id, name: m.name }))}
+      />
+
       <MetricTargetSummary slug="medications" />
 
       {/* v1.12.2 — the assessment is the LAST block on every bespoke

src/components/charts/chart-runtime.ts

@@ -40,4 +40,5 @@ export { SleepStageStackedBar } from "@/components/insights/sleep-stage-stacked-
 export { LabBiomarkerChart } from "@/components/labs/lab-biomarker-chart";
 export { DoseStrengthCurve } from "@/components/medications/dose-strength-curve";
 export { DrugLevelChart } from "@/components/medications/drug-level-chart";
+export { EfficacyChart } from "@/components/medications/detail/efficacy/efficacy-chart";
 export { AssessmentHistoryChart } from "@/components/mental-health/assessment-history-chart";

src/components/insights/medication-efficacy-summary.tsx

@@ -0,0 +1,126 @@
+"use client";
+
+/**
+ * v1.28 — compact, read-only medication-efficacy summary for the Insights
+ * medication surface. Reads the SAME server-computed efficacy DTO the detail
+ * page's "Wirkung" tab reads (no second computation) and shows, per eligible
+ * medication with enough data, a one-line before/after against its target —
+ * strictly association-framed, never a verdict. Each row links through to the
+ * medication's Wirkung tab for the full view.
+ *
+ * Card anatomy per UI-STANDARDS §8: TileHeader + the inherited `px-4 md:px-6`
+ * inset (never re-declared), foreground for content, muted for meta.
+ */
+import Link from "next/link";
+import { Activity, TrendingUp } from "lucide-react";
+import { useQueries } from "@tanstack/react-query";
+
+import { Card, CardContent, CardHeader } from "@/components/ui/card";
+import { TileHeader } from "@/components/insights/tile-header";
+import { queryKeys } from "@/lib/query-keys";
+import { apiGet } from "@/lib/api/api-fetch";
+import { useTranslations } from "@/lib/i18n/context";
+import type {
+  MedicationEfficacyDTO,
+  EfficacyTargetView,
+} from "@/lib/medications/efficacy/build-efficacy";
+
+function primaryWithDelta(
+  dto: MedicationEfficacyDTO,
+): EfficacyTargetView | null {
+  const withDelta = dto.targets.find(
+    (t) => t.primary && t.beforeAfter.present && t.beforeAfter.delta,
+  );
+  return withDelta ?? null;
+}
+
+export function MedicationEfficacySummary({
+  medications,
+}: {
+  medications: { id: string; name: string }[];
+}) {
+  const { t } = useTranslations();
+
+  const results = useQueries({
+    queries: medications.map((m) => ({
+      queryKey: queryKeys.medicationEfficacy(m.id),
+      queryFn: () =>
+        apiGet<MedicationEfficacyDTO>(`/api/medications/${m.id}/efficacy`),
+      staleTime: 60_000,
+    })),
+  });
+
+  if (medications.length === 0) return null;
+
+  const rows = results
+    .map((r, i) => ({ med: medications[i], dto: r.data }))
+    .filter(
+      (
+        x,
+      ): x is {
+        med: { id: string; name: string };
+        dto: MedicationEfficacyDTO;
+      } => !!x.dto && x.dto.eligible,
+    )
+    .map((x) => ({ med: x.med, target: primaryWithDelta(x.dto) }))
+    .filter((x) => x.target !== null);
+
+  return (
+    <Card data-slot="insights-medication-efficacy">
+      <CardHeader>
+        <TileHeader
+          icon={Activity}
+          title={t("medications.efficacy.insights.title")}
+        />
+        <p className="text-muted-foreground mt-1 text-xs">
+          {t("medications.efficacy.insights.subtitle")}
+        </p>
+      </CardHeader>
+      <CardContent className="space-y-3">
+        {rows.length === 0 ? (
+          <p className="text-muted-foreground text-sm">
+            {t("medications.efficacy.insights.empty")}
+          </p>
+        ) : (
+          <ul className="divide-border/60 divide-y">
+            {rows.map(({ med, target }) => {
+              const ba = target!.beforeAfter;
+              const unit = target!.unit ? ` ${target!.unit}` : "";
+              const arrow = (ba.delta?.mean ?? 0) > 0 ? "+" : "";
+              return (
+                <li
+                  key={med.id}
+                  className="flex flex-wrap items-center justify-between gap-x-3 gap-y-1 py-2.5 first:pt-0 last:pb-0"
+                  data-slot="insights-medication-efficacy-row"
+                >
+                  <div className="min-w-0">
+                    <p className="text-foreground text-sm font-medium">
+                      {med.name}
+                    </p>
+                    <p className="text-muted-foreground flex items-center gap-1.5 text-xs">
+                      <TrendingUp aria-hidden="true" className="h-3.5 w-3.5" />
+                      <span>
+                        {target!.label}: {ba.before?.mean}
+                        {unit} → {ba.after?.mean}
+                        {unit} ({arrow}
+                        {ba.delta?.mean}
+                        {unit})
+                      </span>
+                    </p>
+                  </div>
+                  <Link
+                    href={`/medications/${med.id}?tab=wirkung`}
+                    className="text-primary focus-visible:ring-ring shrink-0 rounded-sm text-xs underline-offset-2 hover:underline focus-visible:ring-2 focus-visible:outline-none"
+                    data-slot="insights-medication-efficacy-link"
+                  >
+                    {t("medications.efficacy.insights.link")}
+                  </Link>
+                </li>
+              );
+            })}
+          </ul>
+        )}
+      </CardContent>
+    </Card>
+  );
+}

src/components/medications/detail/efficacy/efficacy-chart.tsx

@@ -0,0 +1,244 @@
+"use client";
+
+/**
+ * v1.28 — the "Wirkung" target chart. Recharts consumer, so it is exported
+ * through `chart-runtime` and loaded via `next/dynamic` at the call site (the
+ * one-shared-chunk rule). Renders the target series over a span around the
+ * medication's start with:
+ *   - a faint population reference band (context, never a goal line),
+ *   - shaded pause bands,
+ *   - a vertical start marker + quiet dose-change markers,
+ *   - the target line,
+ *   - a faint adherence lane on a hidden right axis.
+ * Strictly descriptive — no colour-coded verdict, no "good/bad" zones.
+ */
+import { useMemo } from "react";
+import {
+  ResponsiveContainer,
+  LineChart,
+  Line,
+  XAxis,
+  YAxis,
+  CartesianGrid,
+  Tooltip,
+  ReferenceLine,
+  ReferenceArea,
+} from "recharts";
+import { makeFormatters } from "@/lib/format-locale";
+import { useTranslations } from "@/lib/i18n/context";
+
+export interface EfficacyChartTarget {
+  label: string;
+  unit: string | null;
+  referenceBand: { low: number; high: number } | null;
+  series: { t: string; value: number }[];
+}
+
+export interface EfficacyChartProps {
+  target: EfficacyChartTarget;
+  startMs: number | null;
+  doseChanges: { at: string; label: string }[];
+  pauses: { from: string; to: string | null }[];
+  adherence: { date: string; rate: number }[];
+  timezone: string;
+  startLabel: string;
+  adherenceLabel: string;
+  typicalRangeLabel: string;
+}
+
+const toMs = (iso: string): number => Date.parse(iso);
+
+export function EfficacyChart({
+  target,
+  startMs,
+  doseChanges,
+  pauses,
+  adherence,
+  timezone,
+  startLabel,
+  adherenceLabel,
+  typicalRangeLabel,
+}: EfficacyChartProps) {
+  const { locale } = useTranslations();
+  const fmt = useMemo(
+    () => makeFormatters(locale, timezone),
+    [locale, timezone],
+  );
+
+  const seriesData = useMemo(
+    () =>
+      target.series
+        .map((p) => ({ t: toMs(p.t), value: p.value }))
+        .filter((p) => Number.isFinite(p.t))
+        .sort((a, b) => a.t - b.t),
+    [target.series],
+  );
+  const adherenceData = useMemo(
+    () =>
+      adherence
+        .map((p) => ({ t: toMs(p.date), rate: p.rate }))
+        .filter((p) => Number.isFinite(p.t))
+        .sort((a, b) => a.t - b.t),
+    [adherence],
+  );
+
+  const domain = useMemo<[number, number] | null>(() => {
+    const xs = [
+      ...seriesData.map((p) => p.t),
+      ...adherenceData.map((p) => p.t),
+    ];
+    if (xs.length === 0) return null;
+    return [Math.min(...xs), Math.max(...xs)];
+  }, [seriesData, adherenceData]);
+
+  if (seriesData.length === 0 || !domain) return null;
+
+  // An open pause runs to the chart's right edge (the latest datum); using the
+  // domain max keeps the render pure (no `Date.now()` in the render body).
+  const rightEdge = domain[1];
+  return (
+    <div className="touch-pan-y">
+      <ResponsiveContainer width="100%" height={220}>
+        <LineChart margin={{ top: 8, right: 8, bottom: 0, left: 0 }}>
+          <CartesianGrid
+            strokeDasharray="3 3"
+            stroke="var(--border)"
+            opacity={0.5}
+          />
+          <XAxis
+            dataKey="t"
+            type="number"
+            scale="time"
+            domain={domain}
+            tick={{ fontSize: 11, fill: "var(--muted-foreground)" }}
+            tickLine={false}
+            axisLine={false}
+            tickFormatter={(v: number) => fmt.date(new Date(v))}
+          />
+          <YAxis
+            yAxisId="target"
+            tick={{ fontSize: 11, fill: "var(--muted-foreground)" }}
+            tickLine={false}
+            axisLine={false}
+            width={40}
+            unit={target.unit ? ` ${target.unit}` : undefined}
+          />
+          <YAxis
+            yAxisId="adherence"
+            orientation="right"
+            domain={[0, 100]}
+            hide
+          />
+
+          {/* Population reference band — faint context, labelled "typical
+              range", explicitly NOT a target line. */}
+          {target.referenceBand ? (
+            <ReferenceArea
+              yAxisId="target"
+              y1={target.referenceBand.low}
+              y2={target.referenceBand.high}
+              fill="var(--muted-foreground)"
+              fillOpacity={0.08}
+              stroke="none"
+              label={{
+                value: typicalRangeLabel,
+                position: "insideTopLeft",
+                fill: "var(--muted-foreground)",
+                fontSize: 10,
+              }}
+            />
+          ) : null}
+
+          {/* Shaded pause bands. An open pause runs to now. */}
+          {pauses.map((p, i) => (
+            <ReferenceArea
+              key={`pause-${i}`}
+              yAxisId="target"
+              x1={toMs(p.from)}
+              x2={p.to ? toMs(p.to) : rightEdge}
+              fill="var(--foreground)"
+              fillOpacity={0.06}
+              stroke="none"
+            />
+          ))}
+
+          {/* Adherence lane — faint, hidden right axis. */}
+          <Line
+            yAxisId="adherence"
+            data={adherenceData}
+            dataKey="rate"
+            name={adherenceLabel}
+            type="stepAfter"
+            stroke="var(--chart-4)"
+            strokeWidth={1.5}
+            strokeOpacity={0.5}
+            dot={false}
+            connectNulls
+            isAnimationActive={false}
+          />
+
+          {/* The target series. */}
+          <Line
+            yAxisId="target"
+            data={seriesData}
+            dataKey="value"
+            name={target.label}
+            type="monotone"
+            stroke="var(--chart-1)"
+            strokeWidth={2}
+            dot={{ r: 2, fill: "var(--chart-1)" }}
+            activeDot={{ r: 4 }}
+            connectNulls
+            isAnimationActive={false}
+          />
+
+          {/* Start marker. */}
+          {startMs !== null ? (
+            <ReferenceLine
+              yAxisId="target"
+              x={startMs}
+              stroke="var(--primary)"
+              strokeWidth={1.5}
+              label={{
+                value: startLabel,
+                position: "insideTopRight",
+                fill: "var(--foreground)",
+                fontSize: 10,
+              }}
+            />
+          ) : null}
+
+          {/* Dose-change markers — quiet, dashed. */}
+          {doseChanges.map((d, i) => (
+            <ReferenceLine
+              key={`dose-${i}`}
+              yAxisId="target"
+              x={toMs(d.at)}
+              stroke="var(--muted-foreground)"
+              strokeDasharray="4 4"
+              strokeOpacity={0.6}
+            />
+          ))}
+
+          <Tooltip
+            contentStyle={{
+              backgroundColor: "var(--card)",
+              border: "1px solid var(--border)",
+              borderRadius: "0.5rem",
+              fontSize: "0.8125rem",
+            }}
+            labelFormatter={(v) => fmt.date(new Date(Number(v)))}
+            formatter={(value, name) => {
+              const num = Number(value);
+              const text =
+                name === adherenceLabel
+                  ? `${Math.round(num)}%`
+                  : `${num}${target.unit ? ` ${target.unit}` : ""}`;
+              return [text, String(name)];
+            }}
+          />
+        </LineChart>
+      </ResponsiveContainer>
+    </div>
+  );
+}

src/components/medications/detail/efficacy/efficacy-tab.tsx

@@ -0,0 +1,381 @@
+"use client";
+
+/**
+ * v1.28 — the "Wirkung" tab body: a strictly-descriptive, association-only
+ * view relating a medication to the outcome metric(s)/lab(s) its class is
+ * prescribed to move, around its start. Reads the server-authoritative
+ * efficacy DTO (`GET /api/medications/[id]/efficacy`) and renders it — it
+ * never recomputes a delta, mean, or adherence rate. No verdict, no score, no
+ * "working / not working" language, no dose advice: the copy is numbers +
+ * neutral connective phrasing only, mirroring the adherence-storyline posture.
+ */
+import { useMemo, useState } from "react";
+import dynamic from "next/dynamic";
+import { Activity, TrendingUp } from "lucide-react";
+import { useQuery, useQueryClient } from "@tanstack/react-query";
+
+import { MedicationDetailSection } from "@/components/medications/medication-detail-section";
+import { TileHeader } from "@/components/insights/tile-header";
+import { Card, CardContent, CardHeader } from "@/components/ui/card";
+import { Button } from "@/components/ui/button";
+import {
+  Select,
+  SelectContent,
+  SelectItem,
+  SelectTrigger,
+  SelectValue,
+} from "@/components/ui/select";
+import { ChartSkeleton } from "@/components/charts/chart-skeleton";
+import { queryKeys } from "@/lib/query-keys";
+import { apiGet, apiPut } from "@/lib/api/api-fetch";
+import { useTranslations } from "@/lib/i18n/context";
+import { useAuth } from "@/hooks/use-auth";
+import { DEFAULT_TIMEZONE } from "@/lib/tz/format";
+import type {
+  MedicationEfficacyDTO,
+  EfficacyTargetView,
+} from "@/lib/medications/efficacy/build-efficacy";
+
+const EfficacyChart = dynamic(
+  () =>
+    import("@/components/charts/chart-runtime").then((mod) => ({
+      default: mod.EfficacyChart,
+    })),
+  { ssr: false, loading: () => <ChartSkeleton /> },
+);
+
+export function EfficacyTab({
+  medicationId,
+  active,
+}: {
+  medicationId: string;
+  active: boolean;
+}) {
+  const { t } = useTranslations();
+  const { user } = useAuth();
+  const timezone = user?.timezone || DEFAULT_TIMEZONE;
+  const queryClient = useQueryClient();
+
+  const { data, isLoading } = useQuery({
+    queryKey: queryKeys.medicationEfficacy(medicationId),
+    queryFn: () =>
+      apiGet<MedicationEfficacyDTO>(
+        `/api/medications/${medicationId}/efficacy`,
+      ),
+    enabled: active,
+    staleTime: 60_000,
+  });
+
+  if (isLoading || !data) {
+    return (
+      <MedicationDetailSection
+        titleId="medication-wirkung-heading"
+        title={t("medications.efficacy.title")}
+        dataSlot="medication-wirkung-section"
+      >
+        <ChartSkeleton />
+      </MedicationDetailSection>
+    );
+  }
+
+  // The tab is hidden upstream when ineligible; this is a defensive fallback.
+  if (!data.eligible) {
+    return (
+      <MedicationDetailSection
+        titleId="medication-wirkung-heading"
+        title={t("medications.efficacy.title")}
+        dataSlot="medication-wirkung-section"
+      >
+        <p className="text-muted-foreground text-sm">
+          {t("medications.efficacy.notEligible")}
+        </p>
+      </MedicationDetailSection>
+    );
+  }
+
+  return (
+    <div className="space-y-6" data-slot="medication-wirkung-section">
+      <MedicationDetailSection
+        titleId="medication-wirkung-heading"
+        title={t("medications.efficacy.title")}
+        dataSlot="medication-wirkung-intro"
+      >
+        <div className="space-y-3">
+          <p className="text-muted-foreground text-sm">
+            {t("medications.efficacy.intro")}
+          </p>
+          {data.markers.startSource === "firstReading" ? (
+            <p className="text-muted-foreground text-xs">
+              {t("medications.efficacy.startFallback")}
+            </p>
+          ) : null}
+          {data.markers.start === null ? (
+            <p className="text-muted-foreground text-xs">
+              {t("medications.efficacy.noStart")}
+            </p>
+          ) : null}
+          <RetargetControl
+            medicationId={medicationId}
+            options={data.overrideOptions}
+            isOverride={data.resolution.tier === "override"}
+            onChanged={() =>
+              queryClient.invalidateQueries({
+                queryKey: queryKeys.medicationEfficacy(medicationId),
+              })
+            }
+          />
+        </div>
+      </MedicationDetailSection>
+
+      {data.targets.map((target) => (
+        <TargetCard
+          key={`${target.kind}:${target.key}`}
+          target={target}
+          dto={data}
+          timezone={timezone}
+        />
+      ))}
+
+      <p
+        className="text-muted-foreground text-xs"
+        data-slot="medication-wirkung-disclaimer"
+      >
+        {t("medications.efficacy.disclaimer")}
+      </p>
+    </div>
+  );
+}
+
+function TargetCard({
+  target,
+  dto,
+  timezone,
+}: {
+  target: EfficacyTargetView;
+  dto: MedicationEfficacyDTO;
+  timezone: string;
+}) {
+  const { t } = useTranslations();
+  const startMs = dto.markers.start ? Date.parse(dto.markers.start) : null;
+
+  return (
+    <Card data-slot={`medication-wirkung-target-${target.kind}`}>
+      <CardHeader>
+        <TileHeader
+          icon={TrendingUp}
+          title={target.label}
+          right={
+            target.primary ? (
+              <span className="text-muted-foreground text-xs">
+                {t("medications.efficacy.primaryBadge")}
+              </span>
+            ) : undefined
+          }
+        />
+      </CardHeader>
+      <CardContent className="space-y-4">
+        {target.series.length > 0 ? (
+          <EfficacyChart
+            target={{
+              label: target.label,
+              unit: target.unit,
+              referenceBand: target.referenceBand,
+              series: target.series.map((p) => ({ t: p.t, value: p.value })),
+            }}
+            startMs={startMs}
+            doseChanges={dto.markers.doseChanges}
+            pauses={dto.markers.pauses}
+            adherence={dto.adherence.map((a) => ({
+              date: a.date,
+              rate: a.rate,
+            }))}
+            timezone={timezone}
+            startLabel={t("medications.efficacy.startMarker")}
+            adherenceLabel={t("medications.efficacy.adherenceLane")}
+            typicalRangeLabel={t("medications.efficacy.typicalRange")}
+          />
+        ) : (
+          <p className="text-muted-foreground text-sm">
+            {t("medications.efficacy.noSeries")}
+          </p>
+        )}
+
+        <BeforeAfterCard target={target} minWeeks={dto.minWeeksPerSide} />
+
+        {target.levelShift?.present && target.levelShift.nearStart ? (
+          <p
+            className="text-muted-foreground text-xs"
+            data-slot="medication-wirkung-levelshift"
+          >
+            {t("medications.efficacy.levelShift", {
+              date: formatShort(target.levelShift.at),
+            })}
+          </p>
+        ) : null}
+      </CardContent>
+    </Card>
+  );
+}
+
+function BeforeAfterCard({
+  target,
+  minWeeks,
+}: {
+  target: EfficacyTargetView;
+  minWeeks: number;
+}) {
+  const { t } = useTranslations();
+  const ba = target.beforeAfter;
+  const unit = target.unit ? ` ${target.unit}` : "";
+
+  if (!ba.present || !ba.before || !ba.after || !ba.delta) {
+    const reasonKey =
+      ba.reason === "insufficient_before"
+        ? "medications.efficacy.beforeAfter.needBefore"
+        : ba.reason === "insufficient_after"
+          ? "medications.efficacy.beforeAfter.needAfter"
+          : ba.reason === "no_start"
+            ? "medications.efficacy.beforeAfter.needStart"
+            : "medications.efficacy.beforeAfter.needData";
+    return (
+      <div
+        className="border-border/60 rounded-lg border border-dashed p-3"
+        data-slot="medication-wirkung-beforeafter-empty"
+      >
+        <p className="text-muted-foreground text-sm">
+          {t(reasonKey, { weeks: minWeeks })}
+        </p>
+      </div>
+    );
+  }
+
+  const arrow = ba.delta.mean > 0 ? "+" : "";
+  return (
+    <div
+      className="bg-muted/40 rounded-lg p-3"
+      data-slot="medication-wirkung-beforeafter"
+    >
+      <p className="text-foreground text-sm">
+        {t("medications.efficacy.beforeAfter.summary", {
+          before: `${ba.before.mean}${unit}`,
+          after: `${ba.after.mean}${unit}`,
+          delta: `${arrow}${ba.delta.mean}${unit}`,
+        })}
+      </p>
+      <p className="text-muted-foreground mt-1 text-xs">
+        {t("medications.efficacy.beforeAfter.counts", {
+          beforeCount: ba.before.count,
+          afterCount: ba.after.count,
+        })}
+      </p>
+    </div>
+  );
+}
+
+function RetargetControl({
+  medicationId,
+  options,
+  isOverride,
+  onChanged,
+}: {
+  medicationId: string;
+  options: MedicationEfficacyDTO["overrideOptions"];
+  isOverride: boolean;
+  onChanged: () => void;
+}) {
+  const { t } = useTranslations();
+  const [value, setValue] = useState<string>("");
+  const [busy, setBusy] = useState(false);
+
+  const items = useMemo(
+    () => [
+      ...options.metrics.map((m) => ({
+        value: `metric:${m.key}`,
+        label: m.label,
+      })),
+      ...options.biomarkers.map((b) => ({
+        value: `lab:${b.id}`,
+        label: b.label,
+      })),
+    ],
+    [options],
+  );
+
+  const apply = async (clear: boolean) => {
+    setBusy(true);
+    try {
+      const body: {
+        clear?: boolean;
+        measurementType?: string;
+        biomarkerId?: string;
+      } = {};
+      if (clear) {
+        body.clear = true;
+      } else if (value.startsWith("metric:")) {
+        body.measurementType = value.slice("metric:".length);
+      } else if (value.startsWith("lab:")) {
+        body.biomarkerId = value.slice("lab:".length);
+      } else {
+        setBusy(false);
+        return;
+      }
+      await apiPut(`/api/medications/${medicationId}/efficacy/target`, body);
+      onChanged();
+      if (clear) setValue("");
+    } finally {
+      setBusy(false);
+    }
+  };
+
+  if (items.length === 0) return null;
+
+  return (
+    <div
+      className="flex flex-wrap items-center gap-2"
+      data-slot="medication-wirkung-retarget"
+    >
+      <Activity aria-hidden="true" className="text-muted-foreground h-4 w-4" />
+      <span className="text-muted-foreground text-xs">
+        {t("medications.efficacy.retarget.label")}
+      </span>
+      <Select value={value} onValueChange={setValue}>
+        <SelectTrigger size="sm" className="w-56">
+          <SelectValue
+            placeholder={t("medications.efficacy.retarget.placeholder")}
+          />
+        </SelectTrigger>
+        <SelectContent>
+          {items.map((it) => (
+            <SelectItem key={it.value} value={it.value}>
+              {it.label}
+            </SelectItem>
+          ))}
+        </SelectContent>
+      </Select>
+      <Button
+        size="sm"
+        variant="outline"
+        disabled={busy || value === ""}
+        onClick={() => apply(false)}
+      >
+        {t("medications.efficacy.retarget.apply")}
+      </Button>
+      {isOverride ? (
+        <Button
+          size="sm"
+          variant="ghost"
+          disabled={busy}
+          onClick={() => apply(true)}
+        >
+          {t("medications.efficacy.retarget.reset")}
+        </Button>
+      ) : null}
+    </div>
+  );
+}
+
+function formatShort(iso?: string): string {
+  if (!iso) return "";
+  const d = new Date(iso);
+  return Number.isNaN(d.getTime()) ? "" : d.toISOString().slice(0, 10);
+}

src/components/medications/detail/medication-detail-tabs.tsx

@@ -46,6 +46,8 @@ import { ArrowLeft, Pencil } from "lucide-react";
 import { Button } from "@/components/ui/button";
 import { Tabs, TabsContent, TabsList, TabsTrigger } from "@/components/ui/tabs";
 import { MedicationDetailSummary } from "@/components/medications/medication-detail-summary";
+import { EfficacyTab } from "@/components/medications/detail/efficacy/efficacy-tab";
+import { resolveMedicationTargets } from "@/lib/medications/med-target-map";
 import { MedicationDetailSection } from "@/components/medications/medication-detail-section";
 import { MedicationComplianceBars } from "@/components/medications/card-parts/medication-compliance-bars";
 import { DoseHistoryLedger } from "@/components/medications/dose-history-ledger";
@@ -157,6 +159,7 @@ export interface MedicationDetailSnapshot {
 // the tab strip render and the `?tab=` round-trip validation.
 const TAB_SLUGS = [
   "uebersicht",
+  "wirkung",
   "zeitplan",
   "bestand",
   "verlauf",
@@ -236,6 +239,21 @@ export function MedicationDetailTabs({
   const isGlp1 = !oneShot && medication.treatmentClass === "GLP1";
   const isInjectable = medication.deliveryForm === "INJECTION";
 
+  // v1.28 — the "Wirkung" tab appears only when the medication resolves to a
+  // known outcome target (ATC class prefix → whole-word name inference) and is
+  // not a single-dose med. Same pure resolver the server efficacy builder's
+  // derived tier uses, so the tab's presence agrees with the DTO's eligibility.
+  const hasEfficacyTarget = useMemo(
+    () =>
+      !oneShot &&
+      resolveMedicationTargets({
+        name: medication.name,
+        treatmentClass: medication.treatmentClass,
+        atcCode: medication.atcCode,
+      }) !== null,
+    [oneShot, medication.name, medication.treatmentClass, medication.atcCode],
+  );
+
   const payload = useMemo(
     () => snapshotToWizardPayload(medication),
     [medication],
@@ -254,9 +272,10 @@ export function MedicationDetailTabs({
       TAB_SLUGS.filter(
         (slug) =>
           (slug !== "injektion" || isInjectable) &&
-          (slug !== "zeitplan" || !asNeeded),
+          (slug !== "zeitplan" || !asNeeded) &&
+          (slug !== "wirkung" || hasEfficacyTarget),
       ),
-    [isInjectable, asNeeded],
+    [isInjectable, asNeeded, hasEfficacyTarget],
   );
 
   const requestedRaw = searchParams?.get("tab");
@@ -535,6 +554,16 @@ export function MedicationDetailTabs({
           )}
         </TabsContent>
 
+        {/* WIRKUNG — the per-medication efficacy view: the outcome metric(s)/
+            lab(s) the drug's class targets, over the span around its start,
+            with a before/after comparison + adherence lane. Strictly
+            descriptive; hidden for one-shot + no-target medications. */}
+        {hasEfficacyTarget && (
+          <TabsContent value="wirkung" className="space-y-6 pt-2">
+            <EfficacyTab medicationId={id} active={activeTab === "wirkung"} />
+          </TabsContent>
+        )}
+
         {/* ZEITPLAN — inline edit of the everyday levers: dose times +
             each dose's on-time window, then the Erinnerung card (the
             notifications switch + the reminder grace, folded in from the

src/lib/query-keys/medications.ts

@@ -138,4 +138,13 @@ export const medicationKeys = {
    */
   medicationApiEndpoint: (medicationId: string) =>
     ["medications", medicationId, "api-endpoint"] as const,
+  /**
+   * v1.28 — per-medication efficacy view ("Wirkung")
+   * (`GET /api/medications/[id]/efficacy`), consumed by the detail page's
+   * Wirkung tab and the Insights medication summary. Rides under the
+   * `["medications", id, …]` prefix so an intake mutation (which moves the
+   * adherence lane) reaches it through `medicationDependentKeys`.
+   */
+  medicationEfficacy: (medicationId: string) =>
+    ["medications", medicationId, "efficacy"] as const,
 };