Alopecia Areata

Alopecia Areata is indexed under Dermatologic, Hair Disorders. Also known as AA, alopecia totalis, alopecia universalis.

US prevalence

1 in 500 to 1 in 1,000 people in the United States Source: MedlinePlus Genetics (NLM), Alopecia areata, frequency section last updated June 1, 2018. This figure comes from a professional society, registry, or study rather than a federal source. Label: REPORTED.

ICD-10-CM codes

L63, L63.9

Typical onset

Any age; ~50% before age 20

Course

episodic

Body systems

dermatologic

Sex differences

Equal

Racial and ethnic differences

Comparable across groups

What this page does not establish

These figures describe populations, not individuals, and none of them is a diagnosis or a treatment recommendation. Prevalence estimates are approximate and reflect published ranges. Disparity figures are reported patterns, not causes.

Taxonomy last reviewed 2026-05-19. Each figure on the interactive page carries its own source and retrieval date, which can be later than this review.

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