• botulinum toxin A;
  • hyperhidrosis;
  • iontophoresis


We report two patients with severe palmar hyperhidrosis who responded to BOTOX® delivered not by injection, the usual method of delivery, but by iontophoresis. The Botulinum molecule has been considered too large for delivery into the skin this way. However, other large peptides, both non-ionic and cationic, have been delivered successfully by this method, so we suspected that BOTOX® could in fact be iontophoresed. Our saline-controlled treatment of these two patients with a small iontophoresis unit (Iomed Phoresor II) allowed small volumes of standard BOTOX® dilutions to be used, and demonstrates that iontophoresis can indeed deliver BOTOX® successfully. This has important therapeutic potential for the large number of patients with focal hyperhidrosis. They may be spared painful injections, and in more severe cases, invasive surgery.