Jaw and trapezius botox in Korea: when does it work, what does it cost in Gangnam?

Quick answer: Jaw botox shrinks the masseter and trapezius botox the muscle on top of the shoulders. The injections are quick, but change shows from 4 to 6 weeks and peaks at 3 months, usually after a visitor is home. At Repic Clinic in Gangnam, jaw botox is from KRW 30,000 for 50 units and trapezius from KRW 72,000 for 100 units (September 2026, VAT excluded).

How does jaw botox slim the face?

It leaves the jawbone alone and reduces the bulk of the masseter, the chewing muscle that thickens the angle of the jaw. Botulinum toxin temporarily reduces acetylcholine release where nerve meets muscle, so less force goes into chewing, and a muscle that is used less slowly thins, like an arm after you stop going to the gym. That is why you do not see it straight away. The muscle takes time to shrink.

What if the square jaw comes from the bone itself? Then botox will not change it. If the side of the jaw bulges hard when you clench your teeth, it is closer to the muscular type; if nothing changes when you clench, it is closer to the skeletal type. That distinction is made at the start of the consultation.

When does jaw botox start working, and how long does it last?

You notice it from 4 to 6 weeks, it is most visible around 3 months, and it lasts 4 to 6 months. Unlike wrinkle botox, this is a treatment you wait more than a month for. Once it wears off, the muscle gets used again and slowly comes back, so it is usually repeated every 4 to 6 months. Many people find the muscle returns to its old size more slowly with repeated treatments, though this varies a lot between individuals.

For a short trip, that timing matters. You will likely fly home before the change appears, so the 4-to-6-week check happens after you leave. Keep a note of the brand and units you received; it tells any doctor exactly what was done.

What does trapezius botox do to the shoulder line?

It eases tension in the upper trapezius, the part that rises between the neck and the shoulder, so the shoulder line slopes more gently. The principle is the same as for the jaw, but the area is larger and the muscle helps move the arm and shoulder, so where and how much to inject matters even more. At Repic, body botox at 100 units is the baseline dose, and the distribution is set from the thickness of the trapezius and how much you use your shoulders (exercise, desk and computer habits). Some people with tight, knotted shoulders say the neck feels lighter too, but that is a side benefit, not the purpose of a cosmetic treatment.

Jaw botox vs trapezius botox: what is the difference?

Same product, different muscle, different dose.

• Jaw (masseter) botox: suits an angular jaw from an enlarged masseter, or a masseter built up by grinding or clenching. The baseline is 50 units; a bigger muscle needs more.
• Trapezius botox: suits raised shoulders that make the neck look short, or anyone wanting a softer shoulder line. The baseline is 100 units, priced as body botox, the same as calf botox.
• Both on the same day: possible, and handy on a short stay. The total dose for the day has to be managed, so both areas are planned together.
• Not suitable: during pregnancy or breastfeeding, with a neuromuscular condition, or with a skeletal-type square jaw.

How much do jaw and trapezius botox cost in Gangnam? (September 2026)

Prices are from Repic Gangnam's September 2026 price list and exclude 10% VAT, which is added at payment. The same prices apply to Korean and international patients; the tax-refund scheme for cosmetic procedures is no longer available in Korea. The final figure depends on area and dose, and an exact quote follows diagnosis.

Higher-priced brands do not start faster or last noticeably longer. A large masseter may need more than 50 units, and a thick trapezius more than 100, so the exact amount is confirmed after diagnosis. The full list is on the price list, and the consultation fee is deducted in full if you are treated the same day.

What should you check before treatment, and what are the side effects?

Tell us four things before treatment: whether you are pregnant or breastfeeding, any neuromuscular condition, any blood thinners, and any previous botox and how you reacted. For 4 hours afterwards, do not rub the area or lie down, and skip saunas and exercise that day. With the jaw, tough food can feel harder to chew for the first few weeks; with the trapezius, lifting the shoulder can feel slightly different. Both are mostly temporary. Bruising, swelling, headache and, rarely, left-right asymmetry can occur, and careful dose and injection planning keeps them to a minimum. Difficulty swallowing or breathing, or weakness across the whole body, is rare but means you should contact a doctor straight away. If filler is also planned, botox first and filler 7 to 14 days later gives a more predictable result, though the same day is possible.

How we do it at Repic

What I see in clinic is that diagnosis decides how jaw botox turns out. With your teeth clenched, the doctor feels the masseter for thickness and side-to-side difference, checks the skin with Meta-Vu and Mark-Vu, and settles first whether the jaw is muscular or skeletal. For the trapezius, we ask about how you use your shoulders before setting the distribution. Once brand and dose are chosen, the doctor injects personally and explains the 4-to-6-week check point and home care. The consultation can be held in English, and cards issued abroad are accepted.

Related reading

• Can mouth-corner or nose botox change how your face reads?
• Botox precautions and side effects, explained by the doctor

Repic Clinic Gangnam: B1 & 2F, 318 Gangnam-daero, Gangnam-gu, Seoul (Yeoksam-dong, TOWER837) · +82-2-6952-0312 · Book online

This is general information and does not replace a medical consultation. Results vary with individual condition.