Unilateral hyperhidrosis with accompanying contralateral anhidrosis.

Localized unilateral or segmental hyperhidrosis is a rare form of increased sweat production of unknown origin. Most reported cases have occurred in otherwise healthy people, with none of the typical triggering factors found in essential hyperhidrosis. The localization of segmental hyperhidrosis is usually the forearm or forehead. We report a case of unilateral hyperhidrosis on the right sides of the forehead, and nose, and the palmar surface of the right hand with anhidrosis on the left hand.