Lower relapse rate of botulinum toxin A therapy for axillary hyperhidrosisby dose increase

Background: Primary focal hyperhidrosis is a common condition that gives ri se to functional and emotional problems and may disturb professional and so cial life. Recently, low-dose intracutaneous injections of botulinum toxin A have been shown to induce a temporary anhidrosis, with relapses occurring usually after 4 to 6 months. Objective: To evaluate the short- and long-term effective-ess and possible adverse effects of high-dose botulinum toxin therapy in the treatment of ax illary hyperhidrosis. Design: III an open study, patients with focal hyperhidrosis were treated w ith intracutaneous injections of botulinum toxin A (Botox; Allergan Inc, Ir vine, Calif). A total dose of 200 U of botulinum toxin A was used once per axilla. Patients were observed for up to 15 months. Settings: University medical center. Patients: Twenty-four patients with axillary hyperhidrosis were treated. Th eir ages ranged from 19 to 58 years (mean +/- SD, 34.8 +/- 12.4 years). Main Outcome Measures: Reduction of sweating as assessed by the Minor iodin e-starch test and planimetry of hyperhidrotic areas. Patients were intervie wed at the end of follow-up about their satisfaction with this treatment. Results: Within 6 days, all patients reported cessation of excessive sweati ng. The mean +/- SD area of excessive sweating identified by the Minor iodi ne-starch test decreased from 19.27 +/- 11.95 cm(2) to 0.25 +/- 0.61 cm(2) (P < .001). The mean follow-up was 10.0 +/- 2.8 months (range, 5-15 months) . Four patients (17%) reported a return of axillary hyperhidrosis after 7 t o 10 months. All patients who experienced relapse showed an excellent respo nse to a second treatment. The only adverse effects reported were temporary pain and burning during the injections. No muscular weakness, insensitivit y, or systemic reactions were observed. Conclusions: High-dose botulinum toxin A seems to be as safe as low-dose bo tulinum toxin A in the treatment of axillary hyperhidrosis. The preliminary data suggest a lower rate of relapse.