Alopecia areata: Overview
Alopecia (al-oh-PEE-shah) means hair loss. When a person has a medical condition called alopecia areata (ar-ee-AH-tah), the hair falls out in round patches. The hair can fall out on the scalp and elsewhere on the body.
Alopecia areata can cause different types of hair loss. Each of these types has a different name:
- Alopecia areata (hair loss in patches).
- Alopecia totalis (lose all hair on the scalp).
- Alopecia universalis (lose all hair on the body).
Not everyone loses all of the hair on the scalp or body. This happens to about 5 percent of people.
Hair often grows back but may fall out again. Sometimes the hair loss lasts for many years.
Alopecia is not contagious. It is not due to nerves. What happens is that the immune system attacks the hair follicles (structures that contain the roots of the hair), causing hair loss. This disease most often occurs in otherwise healthy people.
Image used with permission of the American Academy of Dermatology National Library of Dermatologic Teaching Slides.