Alopecia areata

Alopecia areata (AA), also known as spot baldness, is a condition in which hair is lost from some or all areas of the body. It often results in a few bald spots on the scalp, each about the size of a coin. Psychological stress and illness are possible factors in bringing on alopecia areata in individuals at risk, but in most cases there is no obvious trigger. People are generally otherwise healthy. In a few cases, all the hair on the scalp is lost, or all body hair is lost. Hair loss can be permanent or temporary.

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