Decreased sweating; Anhidrosis
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.
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.
Cause of anhidrosis may include:
- Brain tumor
- Certain genetic syndromes
- Certain nerve problems (neuropathies)
- Congenital disorders including ectodermal dysplasia
- Nervous system disorders such as Guillain-Barre syndrome
- Skin diseases or scarring of the skin that block sweat glands
- Trauma to sweat glands
- Use of certain drugs
If there is a danger of overheating, take the following measures:
- Take a cool shower or sit in a bathtub with cool water
- Drink plenty of fluids
- Stay in a cool environment
- Move slowly
- DO NOT do heavy exercise
When to Contact a Medical Professional
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.
What to Expect at Your Office Visit
The provider will perform a physical exam. In emergencies, the health care team will perform rapid cooling measures and give you fluids to stabilize you.
You may be asked about your symptoms and medical history.
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. Other tests to cause and measure sweating may also be done.
A skin biopsy may be done. Genetic testing may be done if appropriate.
Treatment depends on the cause of your lack of sweating. You may be given medicine to cause sweating.
James WD, Elston DM, Treat JR, Rosenbach MA, Neuhaus IM. Diseases of the skin appendages. In: James WD, Elston DM, Treat JR, Rosenbach MA, Neuhaus IM, eds. Andrews' Diseases of the Skin. 13th ed. Philadelphia, PA: Elsevier; 2020:chap 33.
Miller JL. Diseases of the eccrine and apocrine sweat glands. In: Bolognia JL, Schaffer JV, Cerroni L, eds. Dermatology. 4th ed. Philadelphia, PA: Elsevier Saunders; 2018:chap 39.