Why is my Mouth Drooping on One Side when I Had Botox in my Forehead?

If botox is injected or the medicine diffuses towards the inner lower cheekbone or beyond, it may relax the lower eyelid muscle and its pump action will lessen so that fluid may accumulate.  The smile muscle or lip elevators, can also relax so that when one tries to smile or brush teeth, the other side may elevate normally but the side that was affected by botox will not respond giving a sroke-like appearance.  This will all go away with time, but can take up to 12 weeks or more.

This is an unusual but possible side effect of Botox product diffusing into the cheek and muscles that control smiling - it will go away after a period of 3-4 months. Be patient.

If Botox is placed too deeply into the crow's feet, it can cause puffiness under the eyes.  If Botox is placed too far down the crow's feet into the cheek, it can prevent the side of the mouth from lifting so you will have some drooping.  Fortunately, these effects will wear off in a few months.  Ensure you receive treatment from a board certified dermatologist or plastic surgeon to obtain the best possible results from your Botox treatment.