Masseter Botox in Bangkok: Units, Cost and What Jaw Slimming Can't Fix

What Is Masseter Botox?

Masseter Botox is an injection of botulinum toxin type A into the masseter — the thick chewing muscle that runs from the cheekbone to the angle of the jaw. Reducing the muscle's activity causes it to shrink over several weeks, which narrows the lower face.

It is also called jaw Botox, jaw slimming injection, or masseter reduction — all the same procedure.

Why the Masseter Gets Bigger in the First Place

Muscles enlarge when used heavily. Habitual clenching, night-time grinding, frequent gum chewing and a chewy diet all drive this.

Genetics matter too. Some people simply have a larger masseter with no grinding habit.

Muscle, Bone or Fat? Three Different Problems

A wide lower face has three possible causes. Only one responds to Botox.

• Muscle (masseter hypertrophy): The jaw angle feels hard and bulges outward when you clench. This is the case masseter Botox is designed for.
• Bone (mandibular angle prominence): The width is skeletal and does not change when you relax your jaw. Only surgery alters this.
• Soft tissue (buccal fat, laxity): The lower face looks full or heavy but soft to the touch. Botox will not help, and may make laxity more obvious.

In our experience, a meaningful share of patients who book expecting jaw slimming turn out to have a skeletal or soft-tissue pattern instead. We say so rather than treating anyway.

Image: Nabota, manufactured by Daewoong Pharmaceutical (South Korea). Distributed in Southeast Asia by Hyphens Pharma.

How Does Masseter Botox Slim the Jawline?

Botulinum toxin blocks acetylcholine release at the junction between nerve and muscle, so the masseter contracts far less forcefully.

A muscle that is not being loaded loses volume, much as an immobilised limb does. The slimming comes from that disuse atrophy, not from the injection dissolving anything.

This is why the change is gradual — the muscle has to actually shrink.

What the Clinical Evidence Shows

A randomised, triple-blinded trial published in Scientific Reports in 2024 treated 26 women with masseter hypertrophy. Muscle thickness was measured by ultrasound alongside electromyography.

According to the authors, a single low-dose injection "seems to have a clinically subjective and objective effect on masseteric hypertrophy".

The same trial also recorded measurable changes in masticatory performance after a repeat injection. That finding shapes how we space sessions, and we return to it in the safety section below.

How Far the Muscle Actually Shrinks

A comparative study indexed on PubMed Central tracked masseter thickness by ultrasound for a full year after botulinum toxin injection. Thickness fell to its lowest point at the six-month mark and then increased again through month twelve.

That curve explains most of what patients want to know. The result is real, it peaks well after the injection, and it is not permanent.

It Is an Off-Label Use

Jaw slimming is not an approved indication for botulinum toxin in the United States. It is used off-label worldwide, which is worth stating plainly.

The evidence base is nonetheless growing. A randomised phase 2 study of onabotulinumtoxinA for masseter prominence appeared in the Journal of the American Academy of Dermatology in 2024.

Who Is a Good Candidate for Masseter Botox?

You are a good candidate if the angle of your jaw becomes hard and visibly wider when you clench your teeth.

That test — clench, then press your fingers just below and in front of the earlobe — separates muscular width from skeletal width better than any photograph.

Age is not a limiting factor, but skin condition is. Existing laxity should be discussed before treatment, not after.

Who Should Consider Something Else

• Skeletal jaw width: No change on clenching means the width is bone.
• Sagging rather than bulk: A jawline blurred by loose skin needs lifting — see our Ultraformer MPT lifting treatment.
• Very thin lower face: Further reduction can look gaunt.
• Pregnancy or breastfeeding: We do not treat these patients with botulinum toxin.
• Neuromuscular disorders: Myasthenia gravis and similar conditions are a contraindication.

Masseter Botox Compared With the Alternatives

Patients researching jaw slimming usually meet three options at once. They are not interchangeable.

Jaw reduction surgery is the first of them. It removes bone at the mandibular angle, so the change is permanent.

It also carries several weeks of downtime and a two to three month wait for swelling to settle. We do not offer it, and for muscular jaw width it is rarely the proportionate answer.

The two non-surgical options are the ones most patients actually choose between.

Results may vary, and a combination is sometimes better than either option alone.

How Many Units of Botox Do You Need for Masseter Slimming?

Published protocols cluster around 20 to 30 units of onabotulinumtoxinA per side, or 40 to 60 units in total. That is the range we use at Edition Clinic, and for most patients it lands at almost exactly 50 units.

Fifty units is one vial, which is why our masseter pricing starts where it does rather than at a per-unit rate.

Why Bangkok Clinics Quote Such Different Numbers

Much of the confusion is that units are brand-specific and not interchangeable. The Scientific Reports trial used 75 units per masseter — but of abobotulinumtoxinA, where commonly cited conversion ratios sit near 2.5 to 3 units per 1 unit of onabotulinumtoxinA.

Converted, that figure lands back in the 25 to 30 unit range. A clinic quoting "50 units per side" may be using a different product, a different dilution, or a heavier protocol.

In our experience, most patients quoted 80 to 100 units per side elsewhere do not need anything close to that. We dose within the published range and reassess at four to six weeks.

A Systematic Review Found No Single Standard

A 2022 systematic review in the Journal of Cosmetic Dermatology screened 40 articles and analysed 14 studies with samples of ten or more.

The authors noted that no standard guideline exists. That is why the injector's judgement matters more than the quoted number.

Where the Injections Go

Placement matters as much as dose. Injecting too high or too far forward risks affecting the smile muscles.

• Lower third of the muscle: The bulkiest portion, near the mandibular angle.
• Behind the anterior border: Staying posterior protects the risorius and zygomaticus muscles.
• Above the mandibular border: A margin keeps product inside the target muscle.
• Three to five points per side: Spreading the dose gives more even atrophy.

Masseter Botox for Men: Why 100 Units Is Common

Male patients often sit at the upper end of the 20 to 30 unit range per side, since masseter bulk tends to be greater. The bigger difference is what else gets treated in the same visit.

Most of our male patients combine jaw slimming with the forehead and glabella, bringing the total to around 100 units. That is the 8,990 THB package rather than the 4,900 THB one.

For men we reduce bulge at the jaw angle while keeping the mandibular line sharp, rather than producing a narrow V-shape.

What Happens During Treatment at Edition Clinic

The injection takes about five minutes, and the whole visit runs 30 to 45 minutes including consultation. There is no downtime, and many patients treat on the same day they fly.

Most of that window is assessment and marking rather than needle time.

Step by Step

1. Free 1:1 consultation. Our doctor confirms the jaw width is muscular, checks for asymmetry, and reviews your history.
2. Marking. The safe zone is mapped while you clench, on your own anatomy rather than a template.
3. Optional numbing. Cream or ice on request; many patients skip it.
4. Injection. A fine needle delivers the dose across three to five points per side.
5. Aftercare briefing. Stay upright four hours; no facial massage, sauna or intense exercise for 24 hours.
6. Review at 4–6 weeks. We reassess the contour and adjust if needed.

What to Expect Immediately Afterwards

Most patients leave with nothing visible beyond small red pinpricks for an hour or two. Chewing feels normal on day one.

When Will You See Results, and How Long Do They Last?

The first change most patients notice is reduced clenching force at one to two weeks. Visible narrowing develops between four and six weeks and refines for up to three months.

We recommend repeat treatment every three to six months. Results may vary with baseline muscle bulk, chewing habits and dose.

Realistic Timeline

• Days 1–7: No visible change; occasionally a mild jaw ache.
• Weeks 1–2: Clenching feels weaker, morning tightness eases.
• Weeks 4–6: The lower face starts to look narrower. We review here.
• Months 2–3: Peak contour — the fair point for comparison photos.
• Months 3–6: Muscle activity returns. Time to reassess.

Why We Say 3–6 Months Rather Than a Fixed Number

Many clinics quote a flat "four to six months". The imaging data do not support that precision — thickness in the twelve-month study kept falling until month six before rebounding.

In our experience, patients who chew gum daily or clench under stress return closer to three months, while those without those habits often stretch past five. We set expectations by range, not by a marketing number.

Does Masseter Botox Help With Teeth Grinding and Jaw Clenching?

Many patients do report less clenching and less morning jaw tightness after treatment, and there is randomised evidence behind that observation.

But Edition Clinic is an aesthetic clinic. We treat masseter Botox as cosmetic contouring with a functional side benefit, not as a primary treatment for a jaw joint disorder.

That distinction matters, so we make it early rather than after you have paid.

What the Research Supports

A randomised controlled trial indexed on PubMed Central examined low-dose botulinum toxin for nocturnal bruxism and noted that earlier studies had used doses ranging from 20 to 30 mouse units in the masseter, with doses above 20 units also affecting muscle size.

In other words, the aesthetic and functional effects overlap at similar doses, which is why patients treated for jaw slimming often notice the grinding change as a bonus.

Where We Draw the Line

In our experience, the overwhelming majority of patients booking masseter Botox at Edition Clinic come for facial contour, with grinding mentioned only as a secondary concern.

It Does Not Treat the Cause

Botulinum toxin reduces the force the masseter can generate. It does not address why you clench, whether that is stress, sleep-disordered breathing, or occlusal factors.

The behaviour continues; it simply does less damage while the muscle is weakened. Anyone told an injection will cure bruxism is being oversold.

What Are the Side Effects and Risks of Masseter Botox?

Masseter Botox is generally well tolerated, and most side effects are mild and temporary. The risks that matter are dose- and placement-dependent, which is why the injector counts for more than the brand.

Common and Temporary

• Bruising or pinpoint redness: Resolves in a few days.
• Chewing fatigue: Mild tiredness with hard food for two to three weeks.
• Mild aching: A dull jaw ache in the first week.
• Temporary asymmetry: One side may respond faster; usually evens out by week six.

Less Common but Worth Knowing

• Asymmetric smile: If product spreads to nearby expression muscles. Correct placement is the safeguard.
• Paradoxical bulging: A bulge on hard clenching from uneven atrophy; usually correctable at review.
• Hollowing: Over-reduction in a patient without much bulk to begin with.
• More visible skin laxity: Covered in detail below.

The Repeated-Injection Question

The 2024 randomised trial found measurable reductions in masticatory performance and muscle activity after a booster injection, and its authors raise repeated short-interval dosing as a possible harm.

That is why we work within the published dose range and space sessions at three to six months rather than chasing a faster result.

How We Reduce Risk

All injections at Edition Clinic are performed by licensed medical professionals, never by a therapist. Product is sealed and opened in front of you.

Tell your doctor at consultation if you have a neuromuscular condition, take aminoglycoside antibiotics, or are pregnant.

How Much Does Masseter Botox Cost in Bangkok?

At Edition Clinic, masseter Botox costs 4,900 THB for a full 50-unit vial of Nabota, which covers both sides for most patients. Adding the forehead and glabella in the same session moves you to the 100-unit package at 8,990 THB. Consultation is free.

Bangkok clinics price botulinum toxin three different ways — per unit, per area, or per vial — which is why quotes for the same treatment can look nothing alike.

What You Actually Pay

• Nabota 50 units — 4,900 THB: Standard masseter treatment, both sides.
• Nabota 100 units — 8,990 THB: Masseter plus forehead and glabella, or a heavier masseter protocol.
• Premium brand options: Xeomin and Allergan are available at higher price points — see our full Botox treatment page for the complete list.

We price by vial. Fifty units costs 4,900 THB whether it goes into one masseter or both, and there is no per-unit surcharge on top.

Why Cheaper Is Not Always Cheaper

Very low headline prices in Bangkok usually mean one of three things: heavy dilution, a partial vial, or a non-physician injector.

The honest comparison is price per unit of undiluted, genuine product given by a doctor. For brand differences, our detailed guide to Nabota compares it with American Allergan.

What Masseter Botox Doesn't Do: Skin Quality After Jaw Slimming

Masseter Botox changes muscle. It does nothing to the skin sitting on top of it — not texture, not pore size, not firmness.

Most patients never consider this until the contour arrives. A narrower lower face draws attention to skin the wider shape used to distract from.

Two Different Problems, Two Different Categories

• Laxity and sagging: Loose skin along the jawline is a structural issue. The appropriate answer is energy-based lifting such as HIFU, or in some cases volume restoration — not a skin booster.
• Skin quality: Texture, fine lines, enlarged pores and dullness are surface and dermal issues. These respond to regenerative injectables.

Patients sometimes ask whether a skin booster will "tighten" the lower face after jaw slimming. It will not, and we would rather say so.

Where Rejuran Fits

Rejuran is a polynucleotide injectable working at the dermal level to support skin repair, texture and fine lines. It pairs with masseter Botox precisely because the two treat different tissue with no overlap.

All four Rejuran formulations are 9,000 THB per vial, with 10% off two or more in one session. Our Rejuran treatment page sets out which formulation suits which concern.

In our experience, patients who combine the two are typically in their late twenties to mid thirties, treating contour and skin texture as one project.

If Firmness Is the Concern Instead

Patients in their late thirties and beyond more often describe elasticity loss rather than texture. Profhilo, a bio-remodelling treatment at 25,000 THB for 2ml, suits that case better.

Neither changes facial shape, and neither substitutes for lifting. Results may vary.

Why Choose Edition Clinic for Masseter Botox in Bangkok?

Edition Clinic is a Korean-standard aesthetic dermatology clinic in Bangkok, the first overseas branch of Edition Plastic Surgery in Gangnam, Seoul. Every injection is performed by licensed medical professionals in a 1:1 setting.

Across the past three months we have performed more than 100 botulinum toxin treatments, with masseter slimming among the most requested areas.

Korean-Standard Technique, Bangkok Location

Our protocols follow Korean-standard injection technique through our Seoul hospital partnership — the tradition masseter reduction largely comes from. Consultations are in English.

Our Thonglor clinic is on the 4th floor of Marche 150 Thong Lo, ten minutes on foot from BTS Thong Lo exit 3.

Frequently Asked Questions About Masseter Botox

1. Is masseter Botox painful?

Answer: Most patients describe it as a brief pinch rather than pain. A fine needle is used at three to five points per side, and the whole session takes 10 to 15 minutes from first injection to last. Numbing cream or ice is available on request if you would prefer it.

2. Will masseter Botox affect my ability to chew?

Answer: Normal chewing is usually unaffected, though some patients notice mild fatigue with hard or chewy foods for the first two to three weeks. A randomised trial in Scientific Reports recorded measurable changes in masticatory performance after repeated injections, which is why we space sessions at three to six months.

3. Does masseter Botox make your face sag?

Answer: Sagging is not a direct effect of the injection, but reducing muscle volume can make pre-existing skin laxity more visible in some patients. If firmness along the jawline is already a concern before treatment, energy-based lifting rather than more toxin is the appropriate answer.

4. How soon can I fly after masseter Botox?

Answer: There is no downtime and no restriction on flying, so treating on the day you travel is fine. We ask patients to stay upright for four hours afterwards, and to avoid saunas, facial massage and intense exercise for the first 24 hours.

5. Does masseter Botox make a man's face look feminine?

Answer: Not at standard dosing. For male patients the goal is to reduce bulk at the jaw angle while keeping the horizontal mandibular line defined, which reads as a sharper jaw rather than a softer one. Dose sits at the upper end of the 20 to 30 unit range per side.

6. Can I get masseter Botox and forehead Botox in the same session?

Answer: Yes, and it is one of the most common combinations we treat. Masseter slimming uses around 50 units; adding the forehead and glabella typically brings the total to about 100 units, moving the price from 4,900 THB to 8,990 THB.

7. What happens if I stop getting masseter Botox?

Answer: The masseter gradually regains volume and the jawline returns toward its previous width over several months. Published ultrasound imaging shows muscle thickness at its lowest around the six-month mark, then increasing again through month twelve. Nothing is damaged by stopping.

8. Is masseter Botox permanent if I keep doing it?

Answer: No. Some patients find the interval between sessions lengthens after several cycles, because a muscle that has been less active for a long period rebuilds slowly. That is a longer interval rather than permanence, and the published literature has not settled the question.

9. Can masseter Botox fix facial asymmetry?

Answer: It can help when one masseter is more developed than the other, in which case the dose is adjusted per side rather than split evenly. Asymmetry that comes from bone structure or from soft tissue volume will not respond, so the cause has to be identified at consultation first.

10. Is masseter Botox safe during pregnancy or breastfeeding?

Answer: We do not treat patients who are pregnant or breastfeeding, because botulinum toxin has not been adequately studied in these groups. This is a precaution rather than evidence of harm, but it is the standard position at our clinic. Please mention it at consultation.

11. Which is better for a slimmer jawline, masseter Botox or HIFU?

Answer: They address different tissue, so the honest answer depends on your anatomy. Botox reduces the chewing muscle; HIFU targets skin laxity and the SMAS layer. Clench your teeth and feel for a hard bulge at the jaw angle — if it is there, the width is muscular.

12. How many sessions before I see a slimmer jaw?

Answer: Most patients see a visible change from a single session, developing over four to six weeks and refining for up to three months. A second session at three to six months usually deepens the result. Results may vary with baseline muscle bulk and chewing habits.

13. Do I need to stop chewing gum after masseter Botox?

Answer: It helps, though it is not a strict rule. Gum, very tough foods and habitual clenching all keep the masseter working, and a muscle that keeps working rebuilds faster. Patients who chew gum daily tend to return closer to three months than to six.

14. How do I book masseter Botox at Edition Clinic?

Answer: Message us on WhatsApp or LINE and we will arrange a free 1:1 consultation with our doctor. You receive a facial assessment, confirmation of whether the width is muscular, a recommended unit range and a written price before anything is agreed.