Diffuse alopecia on the scalp
This type of rapid baldness may result from an autoimmune disorder, thyroid disorders or anti-cancers drugs. Photo credit: Phototake
Close-up of alopecia areata, showing a hairless patch of scalp on a 36-year-old woman. It is thought to be caused by an immune system abnormality in which the hair follicles are attacked and normal hair formation is disrupted. Photo credit: Phototake
Hair loss on the back of a 3-month-old baby caused by the baby rubbing its head on its bed. The hair will re-grow once the friction is stopped.
Young woman developing excessive facial hairiness known medically as hirsutism; the cause of the disease is not understood although it is thought to be associated with an hormonal disturbance. Photo credit: John Radcliffe Hospital / Photo Researchers, Inc.
This benign condition is caused by an overproduction of melanin and hypertrichosis. It is most common in males soon after puberty.
Bald eyelids of a 12-year-old boy caused by traction alopecia — the gradual loss of hair due to continual force applied to the hair. This hair loss results from trichotillomania, a compulsive disorder in which patients have a strong urge to pull on and pluck hairs leading to hair loss that can sometimes be permanent. Photo credit: Dr. P. Marazzi / Photo Researchers, Inc.
Hair disorders are common and can range from conditions including hair loss and baldness, excessive hair growth, and disorders involving the hair shaft. Causes of hair loss include, but are not limited to, genetic abnormalities, skin disorders, diseases, bacterial infections, hormone imbalances and damaging grooming practices.