The most common form of hair loss, androgenetic alopecia affects roughly 50% of men and a large portion of women above the age of 40 years. The incidence of androgenetic alopecia increases greatly in women following menopause.

Round or oval patches of hair loss on the scalp or in the eyebrows typically signifies alopecia areata. Those who develop this type of loss can progress to total scalp hair loss (alopecia totalis). The cause of alopecia areata is unknown, but it is thought to be an autoimmune disorder.

Telogen effluvium is a common type of hair loss caused when a large percentage of scalp hairs suddenly going into “shedding” phase. The causes of telogen effluvium may be hormonal, stress related, due to poor diet or drug-associated.

Trichotillomania is the name given to the habitual and compulsive plucking of hair from the scalp and/or other hair-bearing areas of the body. Long-term trichotillomania can result in permanent irrevocable damage.

This type of loss is caused by chronic traction (pulling) on the hair follicle and is seen most commonly associated with tight braiding or cornrow hair styles. In most cases, this form of alopecia manifests itself along the hairline.

Loss of hair due to scarring of the scalp is called scarring alopecia. Scarring can result from a number of causes such as injury or trauma to the scalp, burns and diseases. Diseases that may cause permanent loss due to scalp scarring include the autoimmune conditions; lupus erythematosus and scleroderma, and bacterial infections such as folliculitis, fungal infections, and viral infections such as shingles.

Triangular alopecia is loss of hair in the temporal areas that sometimes begins in childhood. Hair loss may be complete, or a few fine, thin diameter hairs may remain. The cause of triangular alopecia is not known, but the condition can be treated medically or surgically.

Typically affecting fair-haired persons, loose anagen syndrome happens when scalp hairs sit loosely in the hair follicles so they can easily be extracted by combing or pulling. It appears in childhood but usually improves as the child ages.