Hyperhidrosis, a disorder that usually begins in childhood or adolescence, is defined as sweating in excess of what is required for normal thermoregulation. This condition may adversely affect one's quality of life by causing emotional disturbance and social embarrassment. Three forms of hyperhidrosis exist: emotionally induced, localized, and generalized. Hyperhidrosis may be either idiopathic or secondary to other diseases, metabolic disorders, febrile illnesses, or drugs. Diagnosis usually is made based on the patient's history and visible signs of excessive sweating. Various effective treatment options are available.