How long does Botox around the lips continue to kick in and can it wear off quicker than other areas as it is the mouth?

Thank you for your question.  Typically people do notice the onset at day 3.  Maximum effect is at day 5 to 7 and then the effects will soften up.  It is normal shortly after injection of the muscles around the mouth to notice difficulty with eating and drinking, even developing temporary drooling and difficulty drinking from a straw.  This will go away by the second week.  The length of action of botox around your mouth should be the typical 3 months.   I hope this helps answer your question and puts your mind at ease. 
Dr. Christine Gosch