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.
Cause of anhidrosis may include:
If there is a danger of overheating, take the following measures:
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.
Your 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; 2018:chap 39.