What does anhidrosis mean?
Anhidrosis is the medical term for the inability to sweat normally — either a complete absence of perspiration or a reduction so severe that the body cannot cool itself effectively. It may be present from birth, as in certain genetic conditions affecting the sweat glands, or it may develop later as a consequence of nerve damage, skin disorders, dehydration, or medications such as anticholinergics. Because sweating is the body's principal mechanism for shedding excess heat, anhidrosis carries a real risk of overheating, heat exhaustion, and potentially fatal heatstroke, so affected individuals must avoid hot environments and strenuous exertion. The word comes from Greek roots meaning 'without sweat' and belongs to a family of related terms including hyperhidrosis, its opposite. Though rarely encountered outside clinical settings, it is a striking example of how a bodily function we take for granted can be essential to survival.
nounThe medical condition of being unable to sweat normally due to absent or severely reduced perspiration, typically resulting from a disorder of the sweat glands or the nerves that control them.
- The complete or near-complete inability to produce sweat, whether congenital, neurological, drug-induced, or caused by damage to the sweat glands themselves.
"Patients taking certain anticholinergic medications are warned about anhidrosis, since the inability to sweat can lead to dangerous overheating."
"The marathon runner was diagnosed with anhidrosis after collapsing in the heat despite drinking plenty of fluids."
"Congenital anhidrosis, often part of a condition called hypohidrotic ectodermal dysplasia, requires lifelong vigilance to prevent overheating."
Rarely pluralized; the condition is usually discussed in the singular even when referring to multiple patients.
"The clinic reported several cases of anhidroses linked to the new medication."
Some people are born unable to sweat at all — for them, a hot summer day isn't just uncomfortable, it's a genuine medical emergency.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of anhidrosis
Anhidrosis derives from Greek: the negative prefix 'an-' ('without') combined with 'hidrōs' ('sweat') and the suffix '-osis,' which denotes an abnormal condition. The same Greek root gives us the related medical terms hidrosis, hyperhidrosis, and hypohidrosis. The word entered English through medical Latin usage, becoming established in nineteenth-century clinical literature as physicians systematized the study of the sweat glands.
Related word forms
How anhidrosis is actually used
A formal, clinical term used almost exclusively in medical contexts; lay speakers would more likely say 'inability to sweat.' In practice, clinicians sometimes use 'hypohidrosis' (reduced sweating) and 'anhidrosis' (complete absence) interchangeably when sweating is markedly diminished.
Easily confused with anhidrosis
Hyperhidrosis is the opposite condition — excessive sweating — whereas anhidrosis is the absence or severe reduction of sweating.