Alopecia areata

Alopecia totalis, loss of all the hair on the head, and alopecia universalis, total loss of all body hair, are more extreme forms of a poorly understood yet common disorder called alopecia areata. For some individuals alopecia areata is short-lived and limited to a few bald patches on the body For others, however, alopecia areata may manifest itself in the prolonged loss of all body hair, including eyebrows and eyelashes. The disorder can affect both male and female individuals at any age, although it is more common among children and young adults. Some cases of alopecia areata seem to be set off by severely stressful life events, yet an exact cause for all cases is unknown. This unpredictable disorder is characterized by the sudden cessation of hair follicle growth, unlike gradual hair loss in common balding.

According to a 1992 American study, one out of every 100 individuals will experience some form of alopecia areata by the age of 50. Additionally, one case in every five instances of alopecia areata can be traced to a family history of the disorder.