Alopecia is the medical term for hair loss that is more than what is normal. It is normal for everyone to lose about 50-100 hairs from the scalp every day. However, bald patches or excessive thinning of hair may be a sign of hair loss. There are several different types of hair loss, each with different characteristics. It is important to be evaluated by a dermatologist to appropriately determine your type of hair loss and how it might best be treated. Sometimes a scalp biopsy may be necessary to make the correct diagnosis, and sometimes a blood test may be necessary to determine the cause of hair loss. Some of the more common types of hair loss are listed below.
Hereditary hair loss, or androgenetic alopecia, is the most common cause of hair loss. It is also called male-pattern baldness when affecting men or female-pattern baldness when affecting women. This condition affects about 80 million adults in the United States. For men, this commonly presents with a receding hairline that can meet with a spreading baldness from the top back of the head. For women, it is more often thinning along the midline of the top of the scalp, like a widened part. The most common treatment options for this type of hair loss include topical minoxidil, which is a non-prescription medication, and finasteride or dutasteride, which is a prescription pill medicine.
Telogen effluvium is a very common form of diffuse hair thinning, which often occurs immediately after pregnancy, after a significant psychological or physical life stressor, after a high fever or major infection, after a major surgery, or in association with thyroid disease or iron deficiency anemia. Often with appropriate treatment of an underlying condition, hair loss can be stopped or may completely reverse.
Alopecia areata is an autoimmune disease that results in round patches of complete hair loss as a result of the immune system attacking the lowest part of the hair follicle. This is common on the scalp, but may affect the eyebrows, eyelashes, or hair on the body. This form of alopecia may be limited to one or a few patches or it can rarely present with complete loss of hair on the entire scalp or entire body. Hair will either regrow or it won’t, but your dermatologist may recommend treatments, usually with injection and topical corticosteroids, to speed up hair regrowth.
Central centrifugal cicatrical alopecia is a form of scarring (permanent) hair loss that most often affects women of African descent in adulthood and presents as a patch of significant hair thinning on the top of the scalp. This may be due to a history of harsh hair treatments such as numerous perms, heat treatments, and hair products, but there is also thought to be a hereditary component. There are other less common forms of scarring alopecia that are seen in people of a variety of descents. These forms of hair loss need to be diagnosed early with treatment started early to prevent the progression of scarring and permanent loss of hair.
Traction alopecia is hair loss that is caused by long term stress on hair follicles, usually from years of wearing hair in a tight ponytail or tight braids. It is best to prevent this type of long term stress on hair so that this does not happen. Once this type of hair loss starts, it tends to be permanent.
Trichotillomania is a medical disorder in which people compulsively and repeatedly pull out their own hair. Some sufferers of this disorder may be compelled to pull out their eyelashes, nose hairs, eyebrows, and other hair on the body, but it is commonly seen on the scalp. A dermatologist can help diagnose this disorder, but a psychiatrist is the most appropriate professional to help treat it.
Ringworm in the scalp is seen in children but hardly ever seen in healthy adults. This disease is contagious and can spread from child to child. Without effective treatment, this disease can cause balding.
Hair loss after radiation therapy or chemotherapy for cancer treatment is common. This type of hair loss can be sudden and can be very significant, but it is often temporary. Sometimes hair regrowth may be a different color or texture.