2 weeks post op Botox to masseter muscles, it has caused the formation of a bulge. Is this normal?

Thank you for your question. Allow 2 weeks for the Botox to settle. Speak with your injecting physician to discuss your results. You may possibly require more Botox to the masseter muscle. Best, 

The most likely scenario is that your masseter muscle has not been fully relaxed.  Some additional doses of Botox may be needed to fully treat the muscle so that it is soft and fully relaxed. 

Hi CF.  It's difficult to say without a before and after picture, but one possibility is that if part of the muscle was relaxed and part was not, you may be noticing the part that was not relaxed.  Injection technique is important when treating this area, so consider a second opinion if you did not achieve the desired outcome.  For an example of Los Angeles before and after pictures for masseter reduction, check the link below.  

This could happen if the muscle wasn't treated in several locations on each side, especially if the Botox was very concentrated. I usually inject in three areas where the masseter is more pronounced, in a triangular configuration. Diluting it can help also. All the best to you! Dr. Clark

What is probably happening is that the remaining muscle that wasn't treated is noticeable. It needs to be uniformly treated. Get some future injections and I bet it gets better. Steven Weiner, MD, Facial Plastic Surgeon, Destin, Fl.

In all likelihood you simply need a second adjusting treatment.  In the initial treatment we like to spread the Botox around but it is common to need a second adjusting treatment.   You have nothing to worry about.  Go and see you doctor and have him give you a second treatment.  One treatment often is simply not enough.  My Best, Dr C

This is a great question.  We use Botox and other neuromodulators to locally decrease various muscles, including the Masseter.  The effects of neuromodulators take differing lengths of time to create a weaker, smaller muscle based upon the size of the muscle at the time of the injection.  It's not unusual to have to "tailor" the treatments (as 1 treatment will not be adequate to reduce the muscle size...4-6 are more likely to be required).  Injection of any neuromodulator would not be able to make any section of the Masseter larger than it was before the injection as the mechanism of action is exactly the opposite.  You have either a small localized bruise within the muscle, which can happen with injections into a muscle, or additional neuromodular treatments are required to further reduce the muscle size...but this shouldn't be done until at least 1 month month after the previous injection.  Hope this helps.