Hyperhidrosis is excessive sweating that may occur over the entire body or only in certain parts, most commonly the face, underarms, palms of the hands and soles of the feet. When it affects the palms and armpits, it may be socially and functionally problematic.

Primary  hyperhidrosis is caused by overactivity of the nerves that carry messages to the affected sweat glands, usually  in the armpits and palms of the hands. These nerves are part of the 'sympathetic' nervous system, which means that they are 'involuntary' or not under our conscious control.

Treatment may be with topical antiperspirants, oral medications, Botox (botulinum toxin) or may involve a surgical procedure known as Endoscopic Thoracic Sympathectomy (ETS). This is a minimally invasive procedure, which interrupts the nerves that supply the sweat glands. Sometimes ETS may be effective in the treatment of problematic facial flushing.