We read with interest the article by Karamfilov et al1 investigating high-dose botulinum toxin type A treatment in 24 patients with axillary hyperhidrosis. The authors emphasize that high-dose botulinum toxin type A treatment seems to be as safe as low-dose treatment and has a lower relapse rate. The mean + SD observation time was 10 + 2.8 months.
The physicians' information for Botox (Allergan Inc, Irvine, Calif [distributed by Allergan AG, Lachen, Switzerland]) recommends in general that dosages should not exceed 6 mU/kg every 2 months. Even in adult spasticity when large muscles have to be treated, no more than 400 mU should be used at 3-month intervals. Furthermore, several dose-dependent subclinical adverse effects on distant muscles and cardiovascular and gastrointestinal pathways have occurred following botulinum toxin type A treatment.2- 4 In a few cases, systemic clinical adverse effects following higher doses of botulinum toxin type A have occurred.5
Schnider P, Moraru E, Kittler H, Voller B, Auff E. High-Dose Botulinum Toxin Type A for Axillary Hyperhidrosis. Arch Dermatol. 2000;136(12):1567. doi: