Botox in masseter slimming one side faster? Is it possible that it is taking effect at different rates? (photo)

The full effect from a Botox treatment can take 1-2 weeks to occur.  When used in the masseter muscle, the slimming effect takes even longer to occur, so I would not be concerned with your results 6 days after the treatment.  

It doesn't work in just 6 days......It takes a whole lot longer for the muscle to atrophy. You must be seeing something else. You should see your injector for a full evaluation of the cause.Best wishes, Dr. ALDO