Botulinum toxin for hyperhidrosis: a review

Primary focal hyperhidrosis is a disorder of idiopathic excessive sweating that typically affects the axillae, palms, soles, and face. The disorder, which affects up to 2.8% of the US population, is associated with considerable physical, psychosocial, and occupational impairments. Current therapeutic strategies include topical aluminum salts, tap-water iontophoresis, oral anticholinergic agents, local surgical approaches, and sympathectomies. These treatments, however, have been limited by a relatively high incidence of adverse effects and complications. Non-surgical treatment complications are typically transient, whereas those of surgical therapies may be permanent and significant. Recently, considerable evidence suggests that botulinum toxin type A (BTX-A) injections into hyperhidrotic areas can considerably reduce focal sweating in multiple areas without major adverse effects. BTX-A has therefore shown promise as a potential replacement for more invasive treatments after topical aluminum salts have failed. This article reviews the epidemiology, diagnosis, and management of primary focal hyperhidrosis, with an emphasis on recent research evidence supporting the use of BTX-A injections for this indication.