Is a masseter botox treatment suitable for treating chubby cheeks in men?

Thank you for your question. If your masseter is responsible for the increased volume in your cheeks, then injecting Botox into this area will slim your face. However, there are other causes of chubby cheeks and a man-shape of the jaw and underlying adipose tissue that can be addressed with skin tightening procedures or dermal fillers.. I recommend you schedule an appointment with a board-certified cosmetic dermatologist who can perform a comprehensive examination and listen to your concerns and goals in detail. From that meeting you should be able to create a customized treatment plan that meets your expectations. Good luck to you!

"Chubby cheeks" could be from extra fat in the cheek area or from the size of the masseter muscle.  An evaluation is needed by an expert injector is needed to determine if Botox would help you achieve your goals.  

Occasionally, yes but each case is best determined by a consult with a professional.   Botox is useful for enlarged, tight cheeks if you  have TMJ but it is not useful if a person simply has excessive adipose (fat) tissue on their cheeks.  This is best remedied with surgery.