Skin & Aesthetics · Contouring
Face Slimming Injections in Seoul: Jaw Botox or Fat Dissolving?
Face slimming injections are cosmetic injections that make the lower face look narrower, either by relaxing an enlarged jaw (masseter) muscle with botulinum toxin or by reducing small pockets of facial fat with fat-dissolving injections. At Hommage Clinic in Gangnam, Seoul, Dr. Kim Hyunbin checks whether muscle, fat or bone shapes your face before recommending one, both or neither.
Quick answer
Face slimming injections narrow the lower face without surgery in two different ways: botulinum toxin shrinks an enlarged jaw (masseter) muscle, and fat-dissolving injections reduce small pockets of soft fat. At Hommage Women's Clinic in Gangnam, Seoul, Dr. Kim Hyunbin first checks whether muscle, fat, bone or loose skin is shaping your face. Injections take about 10–20 minutes; jaw slimming builds over 2–6 weeks and lasts about 3–6 months, while fat reduction usually needs 2–4 sessions.
Key takeaways
- The right injection depends on the tissue: toxin works only on muscle, fat-dissolving injections only on fat. Neither can narrow bone.
- A hard bulge at the jaw angle when you clench points to muscle; soft, pinchable fullness points to fat.
- Neither treatment is instant. Plan at least 6 weeks ahead of an important event.
- In thin or loose faces, removing volume can make hollows or jowls more visible, so less is often more.
Infographic
Face slimming injections in numbers
Injection time
Most people return to work the same day.
Jaw toxin result
The muscle shrinks gradually; judge the result at about 6 weeks.
Jaw toxin lasts
Repeat no more often than every 3 months.
Fat-dissolving sessions
Spaced about 4 weeks or more apart.
Fat reduction visible
After each session, once the swelling settles.
Under-chin response
Improved by at least one grade with deoxycholic acid vs 21% with placebo in FDA trials.
Face slimming injections at a glance
| Key fact | Details |
|---|---|
| Two main types | Botulinum toxin for a bulky jaw muscle; fat-dissolving injections for soft fat pockets |
| Treatment time | Usually 10–20 minutes of injections; around 30–45 minutes with consultation |
| Comfort | Fine needles with ice or numbing cream; fat-dissolving injections sting and burn briefly |
| Sessions | Toxin: one session, repeated every 3–6 months; fat-dissolving: usually 2–4 sessions |
| Downtime | Minimal after toxin; swelling for several days to 2 weeks after fat-dissolving injections |
| Results visible | Toxin: gradually over 2–6 weeks; fat-dissolving: about 4–6 weeks after each session |
| Performed by | A Hommage Clinic physician; treatment plan reviewed by Dr. Kim Hyunbin |
Face slimming injections may suit you if you have
- A square or wide lower face, with a jaw muscle that bulges when you clench
- Jaw muscles enlarged by habitual clenching or teeth grinding
- Soft fullness in the lower cheeks, around the mouth or under the chin, with fairly firm skin
- A wish for gradual, natural-looking change without surgery
Wait or choose another option if you
- Are pregnant or breastfeeding
- Have a neuromuscular condition such as myasthenia gravis, or a past reaction to botulinum toxin
- Have a face that is already thin or sagging, where removing volume can make hollows or jowls more visible
- Have an active skin infection, cold sore or inflamed acne in the area
What are face slimming injections?
Face slimming injections are non-surgical injections that narrow the lower face by reducing what makes it wide: an enlarged chewing muscle or excess soft fat. They are popular in Korea for a softer “V-line” jaw, but they cannot change the width of the bone.
The term covers two quite different treatments:
- Botulinum toxin for the masseter: the masseter is the thick chewing muscle at the angle of the jaw. Relaxing it with small doses of botulinum toxin type A makes it shrink gradually, which slims a square jawline. Our detailed guide is jawline Botox for masseter reduction .
- Fat-dissolving injections: injectable solutions that break down fat cells in small, soft pockets such as the lower cheeks, jowl area or under the chin. See fat-dissolving injections for ingredients and protocols.
Clinics in Seoul also offer “contour” injections that target specific areas for sculpting; our 3D contour injection page explains how these work.
Jaw Botox vs fat-dissolving injections: what is the difference?
The key difference is the target: toxin shrinks muscle, while fat-dissolving injections reduce fat. Choosing the wrong one gives little change, because neither works on the other tissue.
Botulinum toxin (masseter)
- How it works: it blocks the nerve signal to the muscle, so the muscle is used less and slowly gets smaller.
- Suits: a square jaw where the muscle feels hard and bulges when you clench.
- Timeline: slimming builds gradually over 2–6 weeks.
- Duration: typically 3–6 months; with repeated treatment the muscle may stay smaller for longer.
- Downtime: minimal.
Fat-dissolving injections
- How it works: ingredients such as deoxycholic acid disrupt fat-cell membranes, and the body clears the fat over several weeks.
- Suits: soft, pinchable fullness in the lower cheeks, around the mouth or under the chin.
- Timeline: swelling first, then visible slimming about 4–6 weeks after each session; usually 2–4 sessions.
- Duration: destroyed fat cells do not return, so results are long-lasting if your weight stays stable.
- Downtime: swelling and tenderness for several days to about 2 weeks.
Deoxycholic acid is approved in several countries specifically for fat under the chin; its use elsewhere on the face is less studied, so doses are kept small. Many Korean products are mixed formulas, so ask which one will be used.
Which face slimming injection do you need?
The answer comes from a short examination rather than photos alone. The doctor feels your jaw while you clench and relax, pinches the soft tissue of the cheeks and chin, and looks at bone shape, skin firmness and symmetry.
- A hard bulge at the jaw angle when you clench: masseter toxin.
- Soft fullness that does not change when you clench: fat-dissolving injections, if the skin is firm enough to contract afterward.
- Both: the two can be combined, often toxin first and fat reduction a few weeks later, so each effect can be judged.
- A wide jaw bone or a short, recessed chin: injections cannot narrow bone, but adding length with chin filler can make the face look longer and slimmer.
- Sagging jowls: removing volume can make sagging look worse, so lifting usually comes first.
Less commonly, enlarged salivary (parotid) glands in front of the ears widen the face. These need their own assessment. If fullness sits mainly under the jaw, see double chin reduction .
What happens during treatment, and does it hurt?
Both treatments are quick and usually only mildly uncomfortable. Injection time is typically 10–20 minutes, and most people go back to work the same day.
- Your doctor reviews your medical history, medicines and previous treatments, and takes photos.
- Injection points are marked, and ice or numbing cream is applied.
- Toxin: a few small doses are placed deep in the lower part of each masseter, away from the smile muscles. Each feels like a quick sting.
- Fat-dissolving: small amounts are spread through the fat on a grid. A burning or stinging feeling for several minutes is common.
- Gentle pressure and a cold pack reduce bruising and swelling.
How long do face slimming injections last?
Jaw toxin typically lasts about 3–6 months, while fat reduction is long-lasting as long as your weight stays stable. The two follow different timelines.
After masseter toxin, your jaw may tire sooner when chewing tough food within the first days. The slimming appears gradually over 2–6 weeks, so the result is easiest to judge at about six weeks. Once the muscle regains strength, treatment can be repeated, usually no more often than every 3 months.
After fat-dissolving injections, swelling settles over 1–2 weeks and fat reduction becomes visible over the following weeks. Sessions are spaced about 4 weeks or more apart.
Aftercare: do not rub or massage the area that day, and avoid saunas, alcohol and intense exercise for about 24 hours after toxin and for a few days after fat-dissolving injections. Makeup can usually be applied gently after a few hours.
Risks and possible side effects
Face slimming injections are generally well tolerated, but each type has specific risks that you should know before you decide.
- Both types: redness, pinpoint bruising, tenderness and swelling at injection points.
- Masseter toxin: chewing fatigue with tough foods for a few weeks; an uneven smile if toxin reaches the nearby smile muscle; a small bulge of untreated muscle when clenching; and, in thinner or older faces, a hollow look below the cheekbones or more visible jowls. These are temporary. Rarely, the effect spreads further.
- Fat-dissolving injections: marked swelling, numbness, firm nodules and uneven contour; uncommonly, temporary weakness of the lower lip or skin damage if product is placed too shallowly.
Seek urgent care if you have difficulty swallowing, speaking or breathing. Contact the clinic if your smile looks uneven, the skin darkens, blisters or breaks down, or swelling is still increasing after the third day.
Face slimming injections at Hommage Clinic
Hommage Clinic is a women's health and skin clinic in Gangnam, a short walk from Sinnonhyeon Station, and welcomes walk-ins during opening hours. A doctor examines muscle, fat, bone and skin firmness first, then performs the injections.
Alongside botulinum toxin and contour injections, the clinic offers lifting with Ulthera Prime and Tune Face (Accent Prime) for when firmness is the missing piece. See theKorean small face treatmentguide for combined plans, or browse allskin and aesthetic treatments.
Cost depends on the type of injection, the product and dose, and the number of sessions. Cosmetic injections are not covered by Korea's National Health Insurance, and you receive a written quote before treatment. You canbook a consultationto find out which injection fits your face.
Mechanism
How face slimming injections work: muscle vs fat
A wide lower face usually comes from one of three things: a thick chewing muscle at the angle of the jaw, soft fat in the lower cheeks and under the chin, or the shape of the jaw bone itself. Face slimming injections can only change the first two, and each injection works on one tissue only. That is why the examination matters more than the product name.
Botulinum toxin blocks the signal from nerve to muscle. The masseter is used less, and like any muscle that rests, it slowly becomes thinner, which narrows the jaw angle over several weeks. Fat-dissolving injections, most often based on deoxycholic acid, break the outer wall of fat cells; the body then clears the debris, and the treated area slowly flattens. The diagram below shows the difference.
Compare
Jaw Botox vs fat dissolving vs chin filler vs lifting
People searching for a slimmer face in Seoul often compare four non-surgical routes. They are not interchangeable: each one fixes a different cause, and the best plan is sometimes a small amount of two of them rather than a lot of one. Use the cards below as a starting point for your consultation, not as a self-diagnosis.
Jaw Botox
- Fixes: a hard, bulky masseter
- Result: gradual, over 2–6 weeks
- Lasts: about 3–6 months
- Downtime: minimal
Fat-dissolving injections
- Fixes: small, soft fat pockets
- Result: 4–6 weeks after each session
- Lasts: long-term if weight is stable
- Downtime: swelling for days to 2 weeks
Chin filler
- Fixes: a short or recessed chin
- Result: immediate
- Makes the face look longer and narrower
- Adds volume rather than removing it
Lifting (HIFU, RF)
- Fixes: loose skin and early jowls
- Result: builds over weeks to months
- Often added when firmness is missing
- Does not remove fat or muscle
Read more about each option: jawline Botox, fat-dissolving injections, chin filler for V-line shaping and HIFU facial lifting.
Hommage · Gangnam
Hommage Women's Clinic · Gangnam, Seoul
The choice between muscle and fat treatment is made at a face-to-face consultation. Illustrative photo.
Results
Face slimming injection results timeline
The most common surprise after face slimming injections is that nothing seems to happen at first. Jaw toxin needs time for the muscle to thin, and fat-dissolving injections make the area look fuller for a while before it looks smaller. Knowing the two timelines helps you plan around work, holidays or a wedding, and avoid judging the result too early.
Hommage · Gangnam
Hommage Women's Clinic · Gangnam, Seoul
Clenching your teeth with fingers on the jaw angle is a simple first check. Illustrative photo.
Self-check
Square jaw or chubby cheeks? A 1-minute self-check
You can get a rough idea before your visit. Stand in front of a mirror, place your fingertips just in front of the angle of your jaw, and clench your back teeth firmly, then relax. Next, gently pinch the skin of the lower cheek and under the chin. These signs are only a guide; the doctor confirms the cause by examination.
- A firm bulge pops out at the jaw angle when you clench Likely muscle. Masseter toxin is the usual option; you may also clench or grind your teeth.
- Soft, pinchable fullness that does not change when you clench Likely fat. Fat-dissolving injections may help if the skin is firm.
- The jaw feels wide and hard even when relaxed, with no bulge Possibly bone shape. Injections cannot narrow bone; chin length or proportion may be the better focus.
- Skin folds or drops below the jawline when you look down Likely laxity. Lifting usually comes before any volume reduction.
- Swelling in front of the ears that comes and goes, or with meals Possibly the salivary glands. This needs a medical assessment, not a slimming injection.
Aftercare
Face slimming injection aftercare: do's and don'ts
Aftercare is simple, but the first day matters. The aim is to keep toxin where it was placed, limit bruising and swelling, and notice early the rare problems that need a check. You receive written instructions before leaving the clinic.
Do
- Use a wrapped cold pack gently if you have swelling
- Choose softer foods for a few days if your jaw tires
- Sleep with your head slightly raised after fat-dissolving injections
- Apply makeup gently after a few hours
- Take photos at the same angle at 2, 4 and 6 weeks
Don't
- Rub, massage or press hard on the area that day
- Use saunas, hot baths or do intense exercise for about 24 hours (a few days after fat-dissolving)
- Drink alcohol on the day of treatment
- Book a facial, massage or other face treatment in the first week without asking
- Judge the result before 6 weeks
Hommage · Gangnam
Hommage Women's Clinic · Gangnam, Seoul
Gentle cold and no rubbing on the first day help limit swelling and bruising. Illustrative photo.
Natural results
A natural V-line without over-slimming
The Korean “V-line” ideal is a softly tapered lower face, not a hollow one. Volume in the cheeks is part of what makes a face look youthful, so the goal of face slimming injections is to reduce what is excessive while keeping enough support. Removing too much can make the area below the cheekbones look sunken and make early jowls more noticeable, especially after 35 or in naturally slim faces.
How Dr. Kim keeps results natural
- Starting with a moderate dose and reviewing at about 6 weeks before adding more
- Staging combined treatment, usually toxin first and fat reduction later, so each effect can be judged
- Avoiding fat reduction in the mid-cheek, where fat supports the face as it ages
- Suggesting lifting or chin balance instead when removing volume would not help
If you want a plan that combines several treatments, see our facial balancing treatment page.
Hommage · Gangnam
Hommage Women's Clinic · Gangnam, Seoul
The aim is a softer jawline that still looks like you. Illustrative photo.
Evidence
Do face slimming injections work? What the research says
The evidence is uneven. Deoxycholic acid for fat under the chin has been tested in large placebo-controlled trials and is approved for that use in the US and in Korea. Botulinum toxin for the masseter is widely used and supported by many smaller studies, but in many countries it is used off-label for this purpose, so ask whether the product chosen is approved for it. Fat-dissolving injections elsewhere on the face, and mixed “contour” formulas, have much less evidence.
Under-chin fat improved
At least one grade better with deoxycholic acid vs placebo, two trials of over 1,000 adults.
US prescribing information, Kybella, 2015Had swelling
Swelling was the most common side effect of deoxycholic acid (43% with placebo).
US prescribing information, Kybella, 2015Thinner masseter at 1 month
Average reduction in muscle thickness after 24 U per side in 20 Korean adults; ultrasound-guided injection did better.
Bae et al., Toxins, 2020Satisfied with jaw toxin
Small pilot study in Asian patients; 2 had mild chewing fatigue.
Ahn et al., Arch Facial Plast Surg, 2004Traveling to Seoul
Face slimming injections in Seoul for international patients
Jaw toxin fits easily into a short trip: one visit of under an hour, with no real downtime. Fat-dissolving injections are harder to fit into a holiday, because swelling peaks in the first days and further sessions are at least 4 weeks apart. Hommage Women's Clinic is in Gangnam, a short walk from Sinnonhyeon Station (Line 9 and Shinbundang Line).
Before you book
- Send front and side photos of your face and your questions by WhatsApp, KakaoTalk or the contact form, and ask for language support if needed.
- Bring your passport, a list of your medicines, and the name and dose of any toxin or filler you have had before.
- Book early in your stay, so a short check is possible before you leave.
- Avoid scheduling fat-dissolving injections right before photos, a wedding or a flight with a tight event after it.
After you fly home
Take same-angle photos at 2, 4 and 6 weeks and send them to the clinic. If you notice difficulty swallowing, speaking or breathing, seek urgent local care.
Hommage · Seoul
Hommage Women's Clinic · Gangnam, Seoul
Seoul: the clinic is in Gangnam, a short walk from Sinnonhyeon Station. Illustrative photo.
Hommage · Gangnam
Hommage Women's Clinic · Gangnam, Seoul
A good clinic examines your face before naming a product or dose. Illustrative photo.
Choosing well
How to choose a clinic for face slimming injections in Seoul
Gangnam has many clinics offering quick jaw Botox and contour injections. Ask these questions at any consultation, including ours:
- Does a doctor examine my face first? Muscle, fat, bone and skin should be checked by touch, not only from photos.
- Which product, and is it approved? Ask for the brand name of the toxin and the ingredients of any fat-dissolving product.
- How many units or how much product per side? A clear dose makes it possible to adjust next time.
- Who injects? The injections should be given by a licensed physician.
- Is there a review at 4–6 weeks? Results and any asymmetry are checked with photos.
- Do they tell me when not to treat? A thin or sagging face may need lifting instead.
What affects the cost of face slimming injections?
The cost depends on which treatment you need, the toxin brand and number of units, the fat-dissolving product and the size of the area, and how many sessions are planned. Combining toxin with fat reduction, chin filler or lifting changes the total. Cosmetic injections are not covered by Korea's National Health Insurance, and you receive a written quote before treatment.
Your visit
What to expect at your face slimming appointment
01
Assessment
Dr. Kim's team feels your jaw at rest and while clenching, checks cheek and chin fat, skin firmness and symmetry, and takes photos.
02
Your plan
You hear whether muscle, fat or bone is the main factor, which injection fits, the expected timeline and risks, plus a written quote.
03
Injections
About 10–20 minutes with ice or numbing cream. Most people return to work the same day.
04
Review
A check at about 4–6 weeks to compare photos and plan any further session.
Your doctor
Dr. Kim Hyunbin
Associate Director · Skin & Aesthetic Treatments
Dr. Kim chooses between muscle and fat treatment by examining the jaw at rest and while clenching, rather than relying on photos alone. If removing volume could make the face look tired or more sagging, Dr. Kim discusses a lighter dose or lifting instead.
Associate director dedicated to skin and aesthetic procedures, with extensive experience in lifting, botulinum toxin, fillers and laser treatments.
Face slimming injections: frequently asked questions
Do face slimming injections hurt?
Most people feel only brief discomfort. Jaw toxin injections feel like a few quick stings, and fat-dissolving injections cause a burning or stinging feeling for several minutes. Ice or numbing cream is used to make both more comfortable, and any tenderness usually fades within a day or two for toxin and within several days for fat-dissolving injections.
How long do face slimming injections last?
Masseter toxin typically lasts about 3–6 months, after which the muscle slowly regains its size unless treatment is repeated. Fat cells destroyed by fat-dissolving injections do not return, so their effect is long-lasting as long as your weight stays stable. Many people use both: toxin for the jaw muscle and a short course of fat reduction.
How soon will my face look slimmer?
Not immediately. After jaw toxin, the muscle shrinks gradually and slimming builds over 2–6 weeks. After fat-dissolving injections, you first look more swollen for several days to two weeks, and the slimming becomes visible about 4–6 weeks after each session. Plan treatment well ahead of any important event.
Can I combine jaw Botox and fat-dissolving injections?
Yes, if your face has both an enlarged jaw muscle and soft fat. They are often staged, with toxin first and fat reduction a few weeks later, so the doctor can see what each one achieves and avoid over-slimming. Some people also add a small amount of chin filler for balance.
Can face slimming injections make my face sag?
They can make existing sagging more visible in some faces. Reducing muscle or fat removes volume, and if the skin is already loose or the face is thin, hollows below the cheekbones or jowls can show more. Toxin effects are temporary. Your doctor checks skin firmness first and may suggest lifting instead.
Are face slimming injections safe during pregnancy or breastfeeding?
Botulinum toxin and fat-dissolving injections are not recommended during pregnancy or breastfeeding, because their safety has not been established in these situations. It is sensible to wait until you have finished breastfeeding. Facial fullness often changes after pregnancy anyway, so reassessing later gives a more accurate plan.
Can foreigners get face slimming injections in Seoul?
Yes. International patients can be treated at Hommage Clinic; bring your passport for registration. Walk-ins are welcome, or book ahead for a set time. Jaw toxin fits easily into a short trip, while fat-dissolving injections need repeat sessions about a month apart. Contact us before your visit to arrange language support.
How do I know if my wide face is muscle or fat?
Place your fingertips in front of the angle of your jaw and clench your teeth. A firm bulge that pops out suggests an enlarged masseter muscle, which responds to toxin. Soft, pinchable fullness that does not change when you clench suggests fat. A doctor confirms this by examination, and also checks bone shape, skin firmness and the salivary glands.
How many units of Botox are used for the jaw?
The dose depends on the size and strength of your masseter and on the product, because units are not interchangeable between brands. Published studies have commonly used around 24–36 units per side of the toxins they tested. Your doctor tells you the brand and dose per side and records it, so the next treatment can be adjusted.
Will jaw Botox affect chewing or my smile?
Your jaw may tire sooner with tough or chewy food for a few weeks, which most people find mild. An uneven smile can occur if toxin reaches the nearby smile muscle; careful placement deep in the lower masseter reduces this risk, and any effect is temporary. Tell the clinic if your smile looks different.
Can jaw Botox help teeth grinding or clenching?
Many people with a bulky masseter also clench or grind their teeth, and some notice less jaw tension after toxin. Evidence for treating bruxism with toxin is still limited, and it does not replace a dental assessment or a night guard. If grinding is your main concern, see a dentist as well.
Is there downtime after face slimming injections?
After jaw toxin there is almost none; small injection marks fade within hours and most people go back to work the same day. After fat-dissolving injections, expect visible swelling, tenderness and some numbness for several days, sometimes up to two weeks, so plan social events accordingly.
What happens if I stop jaw Botox?
The muscle gradually regains strength and size over several months and the jaw returns toward its original shape. Nothing harmful happens when you stop. With repeated treatments some people find the muscle stays smaller for longer, so the interval between sessions can sometimes be extended.
References
Sources used for this page, reviewed by Dr. Kim Hyunbin. Read our editorial and medical review policy.
- US Food and Drug Administration. KYBELLA (deoxycholic acid) injection: prescribing information. 2015. FDA label
- Allergan Aesthetics. KYBELLA clinical results and dosing (healthcare professional information). Manufacturer page
- Korea Biomedical Review. Allergan Korea receives MFDS approval for double-chin injection Belkyra. August 2017. Article
- Bae H, Kim J, Seo KK, Hu KS, Kim ST, Kim HJ. Comparison between conventional blind injections and ultrasound-guided injections of botulinum toxin type A into the masseter: a clinical trial. Toxins. 2020;12(9):588. DOAJ
- Ahn J, Horn C, Blitzer A. Botulinum toxin for masseter reduction in Asian patients. Arch Facial Plast Surg. 2004;6(3):188–191.
- Ghatge AS, Ghatge SB, Mehta V. A review on bigonial width reduction by botulinum toxin injections in masseter. Bioinformation. 2023;19(3):272–277. Bioinformation
- Allergan. BOTOX treatment for adults with a wide lower face due to masseter muscle prominence: phase 3 protocol (NCT04073303). ClinicalTrials.gov
This page is general information and does not replace a personal consultation. Illustrations are original works of Hommage Women's Clinic, Gangnam, Seoul; photos marked illustrative are not of patients.
Related contouring treatments
Jawline Botox (Masseter Reduction)
Botulinum toxin that slims a square jaw by relaxing an enlarged chewing muscle.
Fat Dissolving Injections
Injections that break down small fat pockets on the face and under the chin.
3D Contour Injection
Targeted contour injections for sculpting specific areas of the face.
Korean Small Face Treatment
Combined plans of injections, lifting and filler for a smaller-looking face.
Double Chin Reduction
Options for fat or loose skin under the chin, matched to the cause.
Facial Balancing Treatment
Filler, toxin and lifting planned together for better facial proportion.
Find out whether muscle or fat is widening your face
Book an assessment in Gangnam. We examine your jaw and cheeks and explain which injection, if any, suits you before treatment.
Hommage Clinic · 4F, Building A, 509 Gangnam-daero, Seoul (near Sinnonhyeon Station) · Mon & Fri 10:00–20:00 · Tue–Thu 10:00–19:00 · Sat 10:00–15:00