diff --git a/frontend/src/app/api/profile.ts b/frontend/src/app/api/profile.ts
index 6eca42d..3100627 100644
--- a/frontend/src/app/api/profile.ts
+++ b/frontend/src/app/api/profile.ts
@@ -1,5 +1,6 @@
 const API_BASE = import.meta.env.VITE_API_BASE_URL;
 const TOKEN_KEY = 'hyfive_token';
+const PET_ID_KEY = 'hyfive_petId';
 
 // ── Types ──────────────────────────────────────────────────────────────────────
 
@@ -143,5 +144,7 @@ export async function activatePet(petId: number): Promise<PetProfileResponse> {
     method: 'PATCH',
     headers: authHeaders(),
   });
-  return parse<PetProfileResponse>(res);
+  const pet = await parse<PetProfileResponse>(res);
+  localStorage.setItem(PET_ID_KEY, String(petId));
+  return pet;
 }
\ No newline at end of file
diff --git a/frontend/src/app/components/HealthLogScreen.tsx b/frontend/src/app/components/HealthLogScreen.tsx
index cbbd2f1..4686d0f 100644
--- a/frontend/src/app/components/HealthLogScreen.tsx
+++ b/frontend/src/app/components/HealthLogScreen.tsx
@@ -15,6 +15,8 @@ import {
 
 type FecalState = '정상' | '무름' | '딱딱함' | '혈변' | '없음';
 
+const CURRENT_PET_ID = Number(localStorage.getItem('hyfive_petId') ?? '1');
+
 const FECAL_TO_API: Record<FecalState, BowelStatus> = {
   '정상': 'NORMAL', '무름': 'SOFT', '딱딱함': 'HARD', '혈변': 'BLOOD', '없음': 'NONE',
 };
diff --git a/frontend/src/app/components/PetProfileScreen.tsx b/frontend/src/app/components/PetProfileScreen.tsx
index 4824439..e005b78 100644
--- a/frontend/src/app/components/PetProfileScreen.tsx
+++ b/frontend/src/app/components/PetProfileScreen.tsx
@@ -254,12 +254,8 @@ export default function PetProfileScreen() {
 
             {/* Vaccine / Prevention */}
             <div>
-              <div className="flex items-center justify-between mb-2">
+              <div className="flex items-center mb-2">
                 <p style={{ fontSize: '13px', fontWeight: 700, color: '#0D2B5E' }}>예방접종 · 투약 현황</p>
-                <button className="flex items-center gap-0.5">
-                  <span style={{ fontSize: '11px', color: '#1B4B8C', fontWeight: 600 }}>전체보기</span>
-                  <ChevronRight size={12} style={{ color: '#1B4B8C' }} />
-                </button>
               </div>
               <div className="bg-white rounded-2xl overflow-hidden" style={{ border: '1px solid #E0E0E0' }}>
                 {vaccineRecords.map((v, i) => (