Treatment of palmar hyperhidrosis with botulinum toxin type A: 44 months of experience

Abstract
Palmar hyperhidrosis (PH) can produce social and occupational difficulties and reduce the quality of life of those who suffer from this kind of problem. When dealing with focal hyperhidrosis, the patients' attitudes and their subjective approaches regarding the process may influence the objective evaluation of the disorder. To evaluate, by means of a scale, the subjective improvement of sweat production after treatment with botulinum toxin type A (BTX-A) in a group of patients with severe, invalidating PH. Patients and methods Over a period of 44 months, 69 patients were treated and followed-up, 27 patients had to be treated twice, and 11 patients required a third application; 80-100 U was injected in each palm. Regional nerve block was performed before the procedure. The patients were asked to evaluate their improvement at 1, 3, 6, 9, and 12 months of baseline. At 1 month, 53.6% of the patients reported an excellent improvement. Three months later, results were still excellent in 33.3% of the patients, and acceptable in 29%. From then on there was a statistically significant decrease of BTX-A effectiveness. A second application was carried out at an interval of 7.5 +/- 2.6 months, and a third one at 9 +/- 4.4 months. The following complications could be observed: transitory weakness of hand muscles in 13 patients, wrist pain in 5 patients, and cramps in 1 patient. Botulinum toxin is an effective alternative for the treatment of severe, invalidating PH. The maximum improvement persists up to 3 months; from then on, the effects slowly diminish. In our experience, there were no statistically significant differences with further applications of BTX-A. The patients' subjective assessment can be used to evaluate the sweat production after treatment with BTX-A in those medical centers where a more objective evaluation becomes difficult or impossible.