Alopecia areata is an autoimmune disorder in which the immune system attacks hair follicles. It affects about 4.7 million people in the United States and occurs equally in men and women. The cause is unknown, but it may be triggered by stress or illness.
The symptoms: The condition can occur in three forms. Alopecia areata commonly causes round, smooth patches of baldness on the scalp, eyebrows, or legs, Dr. Fusco says. Total hair loss on the head is known as alopecia totalis, while hair loss that occurs all over the body is called alopecia universalis. "Some patients have reported that before the bald spot occurred, they felt something in that area—a tingling or an irritation," Dr. Fusco says.
The tests: Observing the pattern of hair loss can usually determine if you have alopecia areata, and blood tests for iron stores, ANAs. and hormones are usually done to rule out underlying conditions that may cause hair loss.
What you can do: Alopecia areata is usually treated with intralesional corticosteroids, Dr. Fusco says. In some cases, minoxidil (Rogaine) may also help. It's also important to reduce stress.