When Does Botox Start Working, and How Long Does It Last? | 보톡스는 언제부터 효과가 나타나고 얼마나 가나요?

🇰🇷 한글

한 줄 요약: FDA 허가사항 기준 보톡스는 주사 1~2일 후 시작해 첫 주 동안 강도가 세지고, 미간 기준 약 3~4개월 가요. 실측 중앙값은 발현 5~6일, 유지 여성 약 4.6개월·남성 약 3.8개월이었어요.

언제부터 나타나나요

FDA 허가사항은 "주사 1~2일 후 화학적 탈신경이 시작되고 첫 주 동안 강도가 증가한다"고 적어요. 180명 시험 실측 중앙값은 여성 5.29일·남성 5.89일이었어요. 3~4일째 그대로여도 정상이니, 2주 뒤 뵙고 판단해요.

얼마나 가나요

허가사항은 미간 기준 "약 3~4개월"이에요. 같은 시험 유지 중앙값은 여성 140.65일·남성 116.61일로 성별이 주된 예측 인자였어요(p<0.0001). 이마 연구(20명)에서 완전 효과 44~56일·부분 효과 99~145일로 서서히 옆어지니, 2개월쯤 조금 움직이는 느낌은 정상이에요.

부위별 용량, 허가사항 그대로

• 미간: 20단위 · 5지점
• 눈가: 24단위 · 6지점
• 이마: 40단위 · 10지점(이마근 20 + 미간 20)

이마근은 눈썰을 올리고 미간 근육은 내려서, 이마만 약하게 하면 균형이 무너져 미간과 함께 허가돼 있어요.

효과는 숫자로 얼마나 확인되나요

미간이 가장 두꺼운 부위예요. 활성 405명 대 위약 132명 시험, 30일째 반응률 80% 대 3%였어요. 눈가·이마도 유의하지만 판정 기준이 달라 숫자를 비교하면 안 돼요.

사각턱은 시간표가 달라요

한국은 2023년 8월 국내 제품이 "양성교근비대"로 세계 최초 허가를 받았고, 용법은 48단위·6지점이에요. 소규모 연구(8명)에서 11주째 가장 크게 감소했고 25주째엔 유의성이 사라져, 2~3개월째에 판단해요.

재시술 간격과 이상반응

3개월보다 자주 맞는 건 평가되지 않았고, 3개월 누적 상한은 360단위예요. 이상반응은 미간 눈꺼풀 처짐 3%, 눈가 부종 1%, 이마 두통 9%(위약 5%)로 눈가가 가장 안전해요. 허가 문구도 "일시적 개선"이에요.

자주 묻는 질문

Q. 며칠 만에 효과를 볼 수 있나요? 1~2일부터 시작해 첫 주 동안 강해져요. 실측 중앙값 5~6일, 판단은 2주 후가 정확해요.

Q. 남자가 더 빨리 없어지나요? 유지 중앙값이 여성 140.65일, 남성 116.61일로 성별이 주된 예측 인자였어요(p<0.0001).

Q. 사각턱 보톡스는 허가받은 시술인가요? 국내는 정식 허가 적응증이에요(2023년 8월, 세계 최초). 제품마다 다르니 확인하세요.

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이 글은 대구 미소의원(경대병원역 1번 출구, 이치학 원장) 정보를 바탕으로 작성했어요. 개인차가 있으니 상담 후 결정하세요. 문의 053-428-2700 · clinicmiso.co.kr

👉 더 자세한 근거는 홈페이지 보톡스 발현·지속 칼럼에 있어요. 관련 글: 피부과 입문 가이드 · 리프팅 체크리스트 · 레이저 후 관리 · 필러 vs 부스터

🇺🇸 English

One-line answer: Per the FDA label, Botox starts working 1-2 days after injection and keeps intensifying over the first week. For glabellar (frown) lines, the label states effects last about 3-4 months, and a measured trial found a median onset of 5-6 days.

When Does It Start Working

The FDA label states injected muscles begin "chemical denervation" one to two days after injection, "increasing in intensity during the first week." A randomized, double-blind trial of 180 people measured a median onset of 5.29 days for women and 5.89 days for men. If you still feel "nothing changed" on day 3 or 4, that's normal — it's just too early to judge. We schedule follow-ups around two weeks out, once the effect has fully settled.

How Long Does It Last

The label states duration for glabellar lines is "approximately 3-4 months." The same trial's measured median duration was 140.65 days (~4.6 months) for women and 116.61 days (~3.8 months) for men — sex was the main predictor of duration (p<0.0001), likely tied to men's thicker, stronger facial muscles.

It also helps to separate "completely immobile" from "still has some effect." A split-face forehead study of 20 people found: - Complete effect: 44-56 days — barely any wrinkling even with movement - Partial effect: 99-145 days — some movement returns, but still shallower than before

So the effect fades gradually rather than vanishing at once. Feeling slight movement around two months in is normal, not a sign it's already gone.

Dosing by Area, Straight From the Label

• Glabellar: 20 Units across 5 sites (2 per corrugator muscle, 1 in the procerus)
• Crow's feet: 24 Units across 6 sites (3 per side)
• Forehead: 40 Units across 10 sites — 20 Units forehead plus 20 Units glabellar

Forehead treatment is labeled to be paired with the glabellar area, since the frontalis raises the brows while the corrugator/procerus lower them — weakening only the "raising" side unbalances things. So a forehead-only request usually gets a glabellar recommendation too, per the label, not for revenue.

How Strong Is the Evidence

Glabellar has the most robust data: in the pivotal trial (405 active vs. 132 placebo), the day-30 response rate was 80% vs. 3% for placebo. Crow's feet and forehead also show significant effects vs. placebo, but each area's "response" criteria differ, so the numbers shouldn't be compared directly.

Masseter (Jaw Slimming) Has a Different Timeline

In Korea, one domestic product was approved in August 2023 for "benign masseteric hypertrophy" — the first such approval worldwide — at 48 Units across 6 sites. Muscle bulk takes longer to shrink than facial lines: a small 8-person study found the largest reduction at week 11 (31.1% during clenching), with significance gone by week 25. So it's judged at 2-3 months, not 2-3 weeks.

Re-treatment Interval and Side Effects

The label notes repeat dosing "more frequently than every 3 months" hasn't been evaluated, and 3-month cumulative dose should generally stay under 360 Units. Trial side effects: - Glabellar (405 patients): eyelid ptosis 3% (vs. 0% placebo) - Crow's feet (526 patients): eyelid edema 1% (vs. 0%) - Forehead (665 patients): headache 9% (vs. 5%); ptosis 2%; brow ptosis 2%

Crow's feet has the cleanest safety record. Botox only blocks nerve signals temporarily — the label itself calls it a "temporary improvement."

FAQ

Q. How soon will I see results? Changes begin at 1-2 days and build through the first week. Measured median onset was 5-6 days; judge the final result around two weeks.

Q. Does it wear off faster in men? Median duration was 140.65 days for women vs. 116.61 for men — sex was the main predictor of duration (p<0.0001).

Q. Is masseter Botox an approved treatment? In Korea, yes — a formally approved indication since August 2023, the first such approval worldwide. Approval varies by product, so it's worth confirming which one is used.

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Based on information from Miso Clinic in Daegu, South Korea (Exit 1 of Kyungpook National University Hospital Station; Dr. Chihak Lee). Results vary. Please consult before deciding. Tel +82-53-428-2700 · clinicmiso.co.kr

👉 Full details and sources on our site: Botox onset & duration column. Related posts: Beginner guide · Lifting checklist · After-laser care · Filler vs booster