The amount of Botox does not depend on race, but there are considerations pertaining to gender.  

Botox treatment is titrated on an individual patient basis. We ascertain the proper amount of solution based on the amount of muscle, not the patient’s race or ethnicity. Males for example, have stronger corrugator muscles in the glabellar region (between the eyebrows) than females. Consequently, males tend to need more Botox than females. It is difficult to make a broad statement about different races and ethnicities in regards to Botox.

The most important point is that if the muscles that control a patient’s facial expression are stronger than usual, that patient will likely need a stronger dose.