斑秃

Alopecia areata is a disease that happens when the immune system attacks hair follicles and causes hair loss. Hair follicles are the structures in skin that form hair. While hair can be lost from any part of the body, alopecia areata usually affects the head and face. Hair typically falls out in small, round patches about the size of a quarter, but in some cases, hair loss is more extensive. Most people with the disease are healthy and have no other symptoms. The course of alopecia areata varies from person to person. Some have bouts of hair loss throughout their lives, while others only have one episode. Recovery is unpredictable too, with hair regrowing fully in some people but not others. There is no cure for alopecia areata, but there are treatments that help hair grow back more quickly. There are also resources to help people cope with hair loss.