There are many types of hair loss. It can affect any part of the body and most commonly affects the scalp.
Hair loss can be localized or diffuse (i.e. involving large areas and/or different areas on the body). Hair may shed, thin out, or simply have poor quality and texture.
There are two main types of hair loss: scarring and nonscarring. Although there is hair loss in both types, the main difference is whether the hair follicle (the body’s working parts to grow hair) is destroyed or not. In scarring alopecia, the hair follicle is destroyed and in non-scarring alopecia, it is not.
Scarring hair loss occurs from several causes such as when the body’s immune system attacks the hair follicles, destroying them and leading to scarring. Unfortunately, once the follicles are scarred, the hair cannot regrow. Some examples of scarring hair loss include:
- Lichen planopilaris: hair loss with inflammation and scaling around the hair follicles
- Dissecting cellulitis of the scalp: a very inflammatory condition of the scalp that leads to hair loss
- Central centrifugal cicatricial alopecia: hair loss in the middle of the scalp with loss of hairs and hair follicle openings in the skin. This condition is more common in the African American population.
- Acne keloidalis nuchae: leads to inflammation and scarring on the back of the scalp/head.
- Autoimmune diseases such as systemic lupus erythematosus: leads to inflammation, scaling, and loss of hair.
In contrast, nonscarring hair loss occurs when the growth cycles of the hair are interrupted, causing the hair to shed, stop growing, or reduce in quality. However, because the hair follicle is not destroyed, there is potential to regrow hair. Nonscarring hair loss can be due to many different causes:
- Alopecia areata: this is an autoimmune condition where the body’s immune system attacks the hair follicle and typically results in round to oval patches of hair loss
- Medications, such as chemotherapy drugs and hormone drugs
- Androgenic alopecia: related to aging and sex hormone abnormalities
- Nutritional deficiencies, e.g. lacking iron
- Hormone alternations, such as overactivity or underactivity of the thyroid.
- Telogen effluvium: related to physical stress (from illness, surgery, pregnancy) and emotional stress
Other causes of hair loss (these can be either scarring or non-scarring):
- Trauma caused by tension on the hair, e.g. consistent wearing of tight braids
- Psychiatric illnesses that result in compulsive hair pulling
- Chemicals from some hair dyes can lead to hair loss.
- Infections of the scalp and hair follicles by bacteria, fungi, and viruses
Treatment for hair loss depends on the diagnosis.
- Inflammation should be treated with anti-inflammatory medications
- Medications that might be causing hair loss should be stopped
- A nutritional deficiency should be corrected
- Minimize hair treatments and hair styles that may injure the hair
Both topical and oral medications can be used in the treatment of alopecia and it depends on the cause of the hair loss.
- Steroids to treat inflammation
- Minoxidil to help hair regrow
- Antibiotic or antifungal medications to treat infections
- Antibiotics or antifungals to reduce infection and inflammation
- Immune suppressantsor oral steroids in those with an autoimmune condition and inflammation
- Finasteride and/or dutasteride to treat androgenic alopecia
Several procedures are directed at improving hair loss:
- Injecting corticosteroids to hair loss sites to treat underlying inflammation
- Microneedling to stimulate hair regrowth
- Hair transplant