Botox for slimming the jaw

Another Botox question on a public forum:

Botox for reduction of masseter. How many units are required for a noticeable difference?

How many units is required for a noticeable difference? Or is it entirely dependent on the individual? I’ve visited a few clinics and I’ve been quoted either 15 or 25 units. I was told by one doctor that with Botox, only a small amount is needed for a difference to be seen. But some clinics recommended a higher dosage as the cost was paid for per unit. Could anyone provide some information on this and what dosage they recommend?

An excellent question.  I’ve wondered this myself and I continue to wonder about what others think about jaw slimming with Botox.  The masseter is the main muscle which can give us a square-ish box-like face.

​I don’t get this opportunity to do this procedure very much.  I’ve only had about 20 patients come in for this issue.   And about 16 patients who come in repeatedly for this feature of Botox at this time.  But I’ve had many more (probably 60 patients) who have had TMJ dysfunction/pain issues which required Botox in the Masseter muscle.

​My worst case scenario is a male patient who had TMJ pain which eventually resolved when we eventually came to the conclusion that 50 Units of Botox on each side helped.  I usually like to do my Botox procedures in a staged fashion where we do a little bit at a time and thus we eventually find the lowest dose that does the right job for us.  He did get jaw slimming features, but that actually was more evident after his third round of 50U of Botox on each side.

​My experience with TMJ masseter muscle Botox helped me come to the realization that masseter/jaw muscle slimming Botox usually has it’s most dramatic effect after the 3rd Botox treatment – assuming no large gaps between treatments.  So this is almost 10 months later.

​Thus for patients coming directly to me for Jaw slimming Botox (cosmetic only).  I try to assess how much of a “rush” patients are in for this to happen.  If they are OK with best results in 10 months.  I usually suggest about 16U-20U on each side to start.  And repeat this process in 3-4 months.  If a person is in a “rush” to get this result, I might start with a higher dose – such as 24-30U and then gradually lower this dose with each subsequent treatment – so I don’t over-correct and get a sunken in jaw look – which in my opinion is not a youthful appearance at all.

​Summary:  Quick answer:  12-50 units per masseter muscle.  Long answer:  It’s not the number of units per session – it might be the number of units done over time that matters most.  I’ve come to realize that the best appearances for masseter muscle slimming is obtained after repeated treatments to this area.  I tell my patients to be patient and wait for the appearance after the 3rd Botox treatment to the masseter area.  Everything in medicine should be individualized – especially Botox!

​Calvin Lee, MD
​Botox injections in Modesto, California

Calvin Lee at Desk smiling ss DSC01401
​Thank you for your question. Without having seen you in person, I’m answering the best I can without physical examination info. My comments are meant for a general public discussion to help others who may have similar concerns. I’m also using my answers to build up library of information for my own patients and also to see how my answers compare with other doctors. There is always much for us to learn from each other. My answers are generalized medical information only, not directed medical advice. For medical advice please see your doctor/surgeon in person.