Improving botulinum toxin therapy for palmar hyperhidrosis: wrist block and technical considerations

Botulinum A exotoxin has become an excellent therapeutic option to treat focal hyperhidrosis, but when the problem affects the palmar region the technique has some drawbacks. Pain with injection is difficult to tolerate and the large dose needed to treat both hands are two concerns, as well as muscle weakness secondary to botulinum toxin diffusion and the possibility of antibody production. All these problems limit the number of patients treated. The author's suggestion is to treat only the dominant hand, after performing a wrist block. The use of a device adapted from a cartridge rubber may help to control the injection depth and the risk of muscular weakness.