“When this happens, the hairs gradually become thinner until they stop growing entirely,” says Michele Green, MD, a New York City–based cosmetic dermatologist. “Having a family member with alopecia areata increases one’s risk for developing the condition,” explains Brittany Craiglow, MD, of Dermatology Physicians of Connecticut and associate adjunct professor of dermatology at the Yale School of Medicine in New Haven. “People who have atopic dermatitis (eczema), asthma, thyroid disease, vitiligo, and Down syndrome are also more likely to develop it.”

Patchy alopecia areataAlopecia totalisAlopecia universalis

Read on to learn more about the types of alopecia areata, how common they are, and what their potential signs and symptoms may be.

Diffuse Alopecia Areata

“Diffuse alopecia areata presents itself as sudden thinning of the hair all over the scalp and is often confused with androgenetic alopecia (male or female pattern hair loss) or telogen effluvium (temporary hair loss due to a trigger),” says Dr. Green.

Ophiasis Alopecia

Nail Changes in Alopecia Areata

Extremely brittle nails, which may splitRed-colored nailsPits or ridges in the nailsTexture changes that are rough and may feel like sandpaper

“Hair loss can be reversible with early detection and treatment, although some forms of hair loss are irreversible,” says Green. She also stresses the importance of seeing a dermatologist for an accurate diagnosis.