Bilateral type 1 complex regional pain syndrome after local nerve blocks for palmar hyperhidrosis.

Botulinum toxin type A (BTX-A) is a recognized treatment for the temporary relief of refractory palmar hyperhidrosis. Unfortunately, intradermal injection of BTX-A can be painful. Several modalities to reduce the pain of injection have consequently been devised. Peripheral nerve blockade with lidocaine before BTX-A treatment of palmar hyperhidrosis is a safe and effective method of pain relief. Anesthesia of the palm can be achieved by injecting 4 to 6 mL of 2% lidocaine without epinephrine subcutaneously around the superficial branches of the radial, median, and ulnar nerves. Use of a short, bevelled needle is recommended to reduce the risk of iatrogenic nerve injury. The risk of nerve injury when using a 30-gauge needle in a conscious patient who can provide feedback concerning nerve puncture is remote.