Alopecia areata Diffuse alopecia Traction alopecia Alopecia is the medical term for hair loss. The most common type is male-pattern baldness, in which hair is lost from the temples and crown.
In female-pattern baldness, hair is usually lost from only the top of the head. Generalized hair loss may occur temporarily after pregnancy or as a result of chemotherapy; other causes include stress, malnutrition, acute illness, and telogen effluvium.
Alopecia areata, caused by the immune system attacking hair follicles, usually causes patchy hair loss.
Other causes of patchy hair loss include ringworm, lichen planus, thyroid problems, and trichotillomania. Treatment depends on the underlying cause.
Medications such as corticosteroids may stimulate hair regrowth. Other options include a hair transplant or wearing a wig.