Alopecia areata shows up as bald patches. The most common areas for alopecia areata are the scalp and the beard, but may involve any body part with hair. There may be one, or multiple bald patches. The patches are usually round in shape and smooth to touch.

Alopecia areata is an autoimmune disease. In this condition, the defense cells of the body – because of a misdirected response – start to destroy hair follicles resulting in bald patches. Heredity and genetics play a significant role in alopecia areata. Patients suffering from alopecia areata very often mention a family member suffering from the same condition.