Botox Sweaty Palms

(59th Annual Meeting of the American Academy of Dermatology) Results of two clinical trials suggest that injections of botulinum toxin type A (Botox) can decrease perspiration at the injected area by inhibiting the release of the neurotransmitter responsible for stimulating the sweat gland in patients with palmar hyperhidrosis (excessive sweating of the palms) and axillary hyperhidrosis (excessive sweating under the arms). In a double-blind study, 19 patients with primary palmar hyperhidrosis were randomly assigned to receive placebo in one palm and a one-time treatment of 15 injections of 0.1 mL of Botox in the other palm. After 28 days, patients' ratings of clinical severity were significantly lower in the palm receiving Botox compared with the palm receiving placebo. All of the patients rated the Botox injections as "successful" at reducing the amount of perspiration, while 12 percent of patients believed the placebo injection had been successful. Patients experienced no serious adverse events, and there was no significant weakness in the hands because the Botox injection did not go deeper than the skin. In another study, 320 patients were randomized in a 3:1 ratio to receive 50 u of Botox or placebo as 2 mL injections in each armpit. After four weeks, 93.8 percent of patients treated with Botox experienced a 50 percent or greater reduction in sweat production, compared with 35.9 percent of patients in the placebo group. The mean percentage in the reduction of sweat production was 83.5 percent in patients receiving Botox and 20.8 percent in patients receiving placebo, and mean patient satisfaction was significantly higher in patients receiving Botox. Patients in both groups experienced a low occurrence of adverse events.--NICHOLAS J. LOWE, M.D., University of California-Los Angeles School of Medicine, Los Angeles, California.