Residual Limb Hyperhidrosis and RimabotulinumtoxinB: A Randomized Placebo-Controlled Study

Objective To investigate the use of rimabotulinumtoxinB (BoNT/B [Myobloc]) compared with placebo in treating hyperhidrosis in the residual limbs of individuals with amputation. Design Randomized, double-blind, placebo-controlled pilot study. Setting Military medical center. Participants Male participants (N=9) with 11 major amputations of the lower limbs and who complained of excessive sweating in their residual limbs were enrolled in the study between September 24, 2008 to October 28, 2011. Participants' lower limbs were randomly assigned to receive injections of either BoNT/B (n=7) or placebo (n=4). Intervention BoNT/B. Main Outcome Measures The primary efficacy variable was a minimum of 50% reduction in sweat production 4 weeks after the injection as measured via gravimetric sweat analysis after 10 minutes of physical exertion. Secondary analyses were performed on prosthetic function and pain. Results All volunteers (100%; 7) in the BoNT/B group achieved a minimum of 50% reduction in sweat production as compared with only 50% (2) in the placebo group. The percent reduction was significantly greater for the BoNT/B group than for the placebo group (-72.7%±15.7% vs -32.7%±39.2%; P<.05). Although both groups subjectively self-reported significant sweat reduction and improved prosthetic function (P<.05 for both), objective gravimetric sweat analyses significantly decreased only for the BoNT/B group (2.3±2.3g vs 0.7±1.1g; P<.05). Neither group reported a change in phantom limb pain or residual limb pain (P>.05 for both). Conclusions BoNT/B successfully reduces sweat production in individuals with residual limb hyperhidrosis, but does not affect pain. No differences were found in perceived effect on prosthetic use between BoNT/B and placebo groups.