Alopecia areata is an autoimmune condition in which the immune system attacks hair follicles, causing well defined round patches of hair loss on the scalp or body. It differs from pattern hair loss in cause and treatment, and can start at any age.
The course is unpredictable: some patches regrow on their own, while others need treatment such as corticosteroids or newer specialist prescribed options. A doctor can confirm the diagnosis, start appropriate therapy and refer to a dermatologist for extensive cases.