Treatment Guide

Botox side effects in Korea: what is normal, what to avoid, and what it costs in Gangnam

Written by Dr. Jay (Yongheon Ha) · Doctor, Repic Clinic

Quick answer: Most botox side effects are temporary and fade as the toxin wears off. The usual ones are a drooping eyelid, left-right asymmetry and a tired jaw when chewing, and the cause is more often the dose plan and injection points than the product itself. Two rules for the first 4 hours: do not rub the area, and do not lie down.

What does botox actually do in the body?

It temporarily blocks the signal where nerve meets muscle, so the muscle contracts less. On the forehead, between the brows and around the eyes, it eases expression muscles that pull too hard. On the jaw, it makes the masseter (the chewing muscle) work less, and the bulk shrinks gradually. You start to see it at 3 to 7 days, the final result settles at 2 weeks, and it fades slowly over 3 to 6 months. Muscle function comes back fully. It does not paralyse anything permanently.

The same product is planned differently for each area. Muscle thickness, skin condition and how uneven the two sides are all change the dose and the injection points, so I do not recommend copying the dose a friend had.

What should you tell the doctor before botox?

Your medications and your medical history. These are checked at the very start of the consultation.

  • Blood thinners and muscle relaxants: warfarin, aspirin and muscle-relaxant drugs can affect bruising and how the toxin acts. Aminoglycoside antibiotics can also strengthen its effect.
  • Pregnancy or breastfeeding: treatment timing is adjusted.
  • Neuromuscular conditions: myasthenia gravis, Lambert-Eaton syndrome and similar neuromuscular junction disorders are listed on the product approval as reasons not to inject.
  • The treatment area: inflammation, infection or an open wound has to heal first.
  • Drinking the night before: it can add to swelling and bruising, so skip it.

What are the side effects of botox?

They come from three places: injection technique, the dose plan, and individual response.

Side effectMain causeUsual course
Drooping eyelid (ptosis)Toxin spreading towards the eyelid-lifting muscle after forehead or frown-line injectionsResolves on its own within weeks to a few months
Stiff or unnatural expressionToo high a dose, or the wrong injection pointEases after 4 to 8 weeks
Left-right asymmetryUneven dosing, muscle thickness differences not accounted forCan be corrected with a touch-up
Headache or neck discomfortChanged tension pattern in the forehead, compensating muscles working harderUsually eases within 1 to 2 weeks
Bruising or swelling at the injection siteInjection near a vessel, blood-thinning medicationAbsorbed within a few days
Weak chewing after jaw botoxMasseter relaxed too muchYou adapt within weeks; ask for a review if it persists

Most of these settle as the toxin wears off. But if a drooping eyelid or clear asymmetry lasts beyond 2 weeks, do not just wait it out: have the clinic that treated you check it. Asymmetry can often be balanced with a corrective injection, and for a drooping eyelid a prescription eye drop is sometimes used to ease the symptom. Rarely, difficulty swallowing or breathing, whole-body weakness or double vision can mean the effect has spread beyond the injection site. That needs a doctor straight away.

If you are visiting Seoul, keep a note of the brand and the units you received. The 2-week mark often falls after you have flown home, and that record is the first thing any doctor will ask for.

Are wrinkle botox and jaw botox different in what to watch for?

Yes. The product is the same, but the target muscle is different, and so is what a poor result looks like.

  • Wrinkle botox: targets the expression muscles of the forehead, between the brows and around the eyes. Change shows in 3 to 7 days and is final at 2 weeks. The warning signs are a drooping eyelid or brows sitting oddly; too much in the forehead makes the eyes feel heavy.
  • Jaw (masseter) botox: targets the masseter. You notice it from 4 to 6 weeks and it is most visible at 3 months, so if there is a fixed date, like a wedding, count backwards. Some chewing fatigue early on is common, and if a hollow look to the cheeks worries you, the dose is planned lower.
  • When it is not suitable: during pregnancy or breastfeeding, with a history of neuromuscular disease, or with inflammation in the area. If a wide jaw comes from the bone, botox will not change it.

Why do the first 4 hours after botox matter so much?

That is when the toxin settles where it was placed. Rubbing or massaging during that window can push it into a neighbouring muscle and weaken the wrong spot. Avoid lying down or hanging your head low for those 4 hours too. Saunas, hot rooms like a jjimjilbang and hard exercise raise body temperature and blood flow on the day, which may affect spread, so leave them until tomorrow. A little redness or stinging at the injection points usually fades within hours.

Can you get botox and filler on the same day?

You can. One relaxes muscle; the other adds volume. Their mechanisms do not overlap. Put both into the same area at once, though, and the way the filler settles can change. Botox first and filler 7 to 14 days later makes the result more predictable. If you only have one day, the areas are split in the plan.

Filler risk depends heavily on the area. For higher-risk areas such as between the brows and the nose, check these four things when choosing a clinic:

  • Genuine, KFDA-approved filler, with the box and sticker shown to you
  • Injection only after the vessel map of the area is assessed; between the brows, the nose and the smile lines carry a high complication risk if a vessel is injured
  • Hyaluronidase, the dissolving enzyme for emergencies, kept on hand at all times
  • A doctor doing the injecting personally

Repic Clinic in Gangnam has all four in place.

How much does 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.

Treatment (per session, KRW)Price (VAT excluded)
Jaw (masseter) botox, 50 unitsDomestic 30,000 · Coretox 60,000 · Xeomin 100,000 · Allergan 190,000
Wrinkle botox, 1 area (forehead, frown lines or crow's feet)Domestic 20,000 · Xeomin 49,000
Wrinkle botox, 3 areas (forehead + frown lines + crow's feet)Domestic 54,000 · Xeomin 130,000 · Allergan 170,000

A pricier brand does not change much about onset or how long it lasts. A large masseter may need more than 50 units, and the cost rises with it. The full list is on the price list, and the consultation fee is deducted in full if you go ahead the same day.

How we do it at Repic

Botox problems usually start with the plan, not the product. So in consultation I ask you to make several expressions and watch which muscles pull, how hard, and whether the two sides differ. Brand and dose are chosen after checking the skin with Meta-Vu and Mark-Vu. I do the injections myself. The 2-week check and home care are explained on the spot, and the consultation can run in English. Who the doctors are and what they treat is on the about page.

Related reading

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.

Related treatments

Frequently asked questions

How long does a droopy eyelid from botox last?

It is rare and happens when toxin from forehead or frown-line injections spreads towards the muscle that lifts the eyelid. Most cases resolve on their own within weeks to a few months, as the toxin wears off. If opening your eye is still hard after 2 weeks, or the two sides look clearly different, have the treating clinic, such as Repic Clinic in Gangnam, check it.

Can I get botox and filler on the same day?

Yes. Botox relaxes muscle and filler adds volume, so the two do not interfere. Injected into the same area at once, though, the filler may spread differently, so the recommended order is botox first and filler 7 to 14 days later. At Repic Clinic in Gangnam the order and gap are planned area by area.

How many days does botox take to kick in?

Change starts 3 to 7 days after injection and the final result shows at 2 weeks. It lasts 3 to 6 months. Jaw botox is slower because it works by shrinking the muscle: you notice it from 4 to 6 weeks and it is most visible around 3 months. If asymmetry remains at 2 weeks, a touch-up is discussed.

Is it normal for chewing to feel weak after jaw botox?

Yes, early on. As the masseter relaxes, tough food can feel like more work, and most people adapt within a few weeks. If there is pain as well, or the discomfort drags on, the dose and injection points need another look, so it is worth having the doctor at Repic Clinic in Gangnam check it.

Can I work out or go to a sauna after botox?

Not on the same day. Raised body temperature and blood flow may let the toxin drift into a neighbouring muscle. For 4 hours after treatment, do not rub or massage the area, and avoid lying down or bending your head low. From the next day, most people have no restrictions on normal activity.