alopecia areata /er′ē·ā″tə/ , a disease of unknown cause in which sudden well-defined bald patches occur. The bald areas are usually round or oval and located on the head and other hairy parts of the body. Hairs that look like exclamation points can sometime occur at a bald patch’s edges. The condition is usually self-limited and often clears completely within 6 to 12 months without treatment. Recurrences are common. Anxiety and stress are common precipitating factors. Compare alopecia totalis, alopecia universalis.
