The improvement generally lasts about 3 to 4 months before the effect gradually fades and muscle action returns. It is anticipated that the average patient will require reinjection at various intervals. Excessive sweating can be alleviated with injections of a highly diluted form of botulinum toxin directly into the underarm skin or skin on the palms and soles of the hand or foot. There it paralyzes the sweat glands of the skin which are responsible for excessive perspiration. A single treatment session can provide months of relief, and experts believe that injections can be repeated indefinitely once or twice a year to maintain dryness.
Side effects are minimal and typically relate to the local injection.
Soreness or mild bruising, while uncommon, may occur around the injection site. Makeup may be worn after treatment, but care should be taken to avoid pressing or massaging the area for several hours. In rare instances, patients may develop temporary weakness of the neighboring muscles, a temporary droopy brow or eyelid, or a headache.