An abnormal lack of sweat in response to heat may be harmful, because sweating allows heat to be released from the body. The medical term for absent sweating is anhidrosis.

Decreased sweating; Anhidrosis

Anhidrosis sometimes goes unrecognized until a substantial amount of heat or exertion fails to cause sweating.

Overall lack of sweating can be life threatening because the body will overheat. If the lack of sweating happens in a small area only, it is usually not as dangerous.

• Burns
• Certain genetic syndromes
• Certain nerve problems (neuropathies)
• Congenital disorders including as ectodermal dysplasia
• Dehydration
• Neurologic disorders such as Guillain-Barre syndrome
• Skin diseases that block sweat glands
• Trauma to sweat glands
• Use of certain drugs

If there is a danger of overheating, take a cool shower or sit in a cool bathtub and drink plenty of fluids. Remain in a cool environment. Move slowly during hot weather. Avoid heavy exercise and hot foods.

Call your health care provider if you have a general lack of sweating or an abnormal lack of sweating when exposed to heat or strenuous exercise.

The doctor will perform a physical exam. In emergencies, the health care team will perform rapid cooling measures and give you fluids to stabilize you.

Your doctor may ask you questions about your symptoms and medical history. You may be given drugs to cause sweating.

You may be asked to wrap yourself in an electric blanket or sit in a sweatbox while the health care team watches your body's reaction.

A skin biopsy may be done.