Treatment of idiopathic palmar hyperhidrosis with botulinum toxin. Report of 23 cases and review of the literature

Background: Botulinum toxin represents a novel therapeutic option for idiopathic palmar hyperhidrosis. However, so far there is no consensus on the way to administer botulinum toxin in this indication. Moreover, its use is limited by severe pain during the injections, especially with subepidermal injections close to 'free nerve endings'.

Objectives: To analyze the effectiveness and tolerability of intracutaneous injections of botulinum toxin after nerve blocks and to review the techniques of injections and the results reported by other groups.

Methods: Twenty-three adult patients with refractory palmar hyperhidrosis were treated with intracutaneous injections of botulinum toxin after ulnar and median nerve blocks. Patients were followed up on a monthly basis.

Results: In all patients botulinum toxin abolished sweating in the injected areas within 1 week. Anhidrosis lasted for 4-13 months. The intensity of pain was rated as absent (n = 13), mild (n = 8) or moderate (n = 2). Other side effects included hematoma (n = 2) and pain consecutive to nerve block (n = 1).

Discussion: Intracutaneous injections of botulinum toxin after median and ulnar nerve block represent an effective and mildly painful technique to treat palmar hyperhidrosis and may be as safe as subepidermal injections.