Treatment of focal hyperhidrosis with botulinum toxin type A. Brief overview of methodology and 2 years' experience

Focal hyperhidrosis is a relatively common condition in which patients experience excessive sweating, usually of the palms, axillae, face or feet. Until recently the only effective treatment option for this chronic condition was surgery. We aimed to evaluate the efficacy and tolerability of botulinum toxin type A (BTX-A) in the treatment of patients,vith hyperhidrosis, establishing optimum dosages and methods of administration. One hundred and seventy patients with focal hyperhidrosis were referred for treatment, the majority with palmar and axillary hyperhidrosis. The iodine-starch test was used to locate and show the extent of the hyperhidrotic area. Using a template to mark the injection sites, 2 U doses of BTX-A were injected intradermally at regular intervals. Patients received either 0.5 or 0.8 U/cm(2), with regional anaesthesia if required. The iodine-starch test and measurements of evaporation were used to assess efficacy. The majority of patients reported a marked reduction in sweating. About one-third of the patients who received BTX-A 0.5 U/cm(2) requested supplementary small injections into islands of skin where they experienced residual sweating. As a result, the standard dose was increased to BTX-A 0.8 U/cm(2). The median duration of treatment effect was 10 months (range, 3 to >14 months). The effectiveness of BTX-A was not reduced by repeated use. BTX-A treatment was well tolerated by all patients. In conclusion, chemical sudomotor denervation with BTX-A should be recommended before surgical sympathectomy for the treatment of focal hyperhidrosis. Eur J Neurol 6 (suppl 4):S117-S120 (C) Lippincott Williams & Wilkins.