Alopecia areata is a common disease that results in the loss of hair on the scalp and elsewhere on the body. There are three types of alopecia areata; alopecia areata, alopecia areata totalis and alopecia areata universalis.

Alopecia areata universalis is the rarest form of alopecia areata and presents itself as the loss of hair over the entire scalp and body.
 
In all forms of alopecia areata, the hair follicles remain alive and are ready to resume normal hair production whenever they receive the appropriate signal. In all cases, hair regrowth may occur even without treatment and even after many years.