What is alopecia areata?

Alopecia areata is a condition that causes a person's hair to fall out. (Alopecia is the medical term for hair loss; there are various types of alopecia, including alopecia areata.)

Alopecia areata is an autoimmune disease, where a person's immune system attacks the body, in this case, the hair follicles. When this happens, the person's hair begins to fall out, often in clumps the size and shape of a quarter. The extent of the hair loss varies; in some cases, it is only in a few spots. In others, the hair loss can be greater. On rare occasions, the person loses all of the hair on his or her head (alopecia areata totalis) or entire body (alopecia areata universalis).

It is believed that the person's genetic makeup may trigger the autoimmune reaction of alopecia areata, along with a virus or a substance the person comes into contact with.

Alopecia areata is an unpredictable disease. In some people, hair grows back but falls out again later. In others, hair grows back and remains. Each case is unique. Even if someone loses all of his or her hair, there is a chance that it will grow back.

Who gets alopecia areata?

Anyone can develop alopecia; however, your chances of having alopecia areata are slightly greater if you have a relative with the condition . In addition, alopecia areata occurs more often among people who have family members with autoimmune disorders such as diabetes, lupus, or thyroid disease.

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