Hair Loss (Alopecia)
What is it?
Hair loss of any sort is called alopecia—be it normal male-pattern baldness (androgenic alopecia, or AGA) that commonly occurs as men age, or abnormal hair loss associated with certain diseases, hormonal disturbances, or treatments such as chemotherapy. There are two general types of alopecia: scarring and non-scarring. In scarring alopecia, the hair follicles that support the hair shaft are destroyed by an underlying condition, so that hair loss is irreversible. In nonscarring alopecia (which includes AGA and alopecia areata), the follicles are preserved, so that regrowth of lost hair remains a possibility. Alopecia has many causes, all of which may affect both sexes.
What Causes It?
- An inherited change that normally occurs with age (AGA).
- Following childbirth, women may experience a several month-long period of increased hair shedding (telogen effluvium).
- An autoimmune response (alopecia areata).
- Bacterial or fungal infections (when severe, may cause scarring and permanent hair loss).
- Cutaneous (skin) discoid lupus or scleroderma (scarring alopecia).
- Chemotherapy drugs (diffuse hair loss with temporary complete baldness).
- Other drugs including corticosteroids, testosterone, heparin, occasionally cholesterol-lower ing drugs, and antithyroid agents (increased rate of hair shedding).
- Malnutrition (especially inadequate protein intake), digestive malabsorption, anorexia nervosa, rapid weight loss, or chronic illness.
- Rare congenital and developmental defects.
- Chemical and physical agents, such as acids, bleach, burns, freezing, or radiation (including x-rays and radiotherapy for cancer).
- Poisoning with toxic levels of arsenic, bismuth, boric acid, and vitamin A.
Prevention
- Hair shaft breakage may be prevented by not overprocessing hair with coloring agents or procedures such as permanent waving or straightening.
Diagnosis
- Alopecia can usually be diagnosed by examination of the characteristic patterns of hair loss.
- More extensive medical tests are warranted when a pathological condition is thought to cause hair loss.
How to Treat It
- Any underlying medical condition causing alopecia needs to be diagnosed and treated.
- Treatment for AGA is not necessary, although a number of methods can restore cosmetic appearance.
- The topical medication minoxidil often slows the loss of hair and may lead to regrowth of some hair.
- Men may benefit from the prescription oral drug finasteride, which causes some hair growth in most users. (Because finasteride may cause birth defects, it is not prescribed for women).
- Hair gels, permanent waves, wigs, hair weaves, hair transplants, or surgery to reposition existing portions of the scalp are other methods to consider.
When to Call a Doctor
- Although it is normal to shed 50 to 100 hairs a day, consult your doctor or dermatologist if you notice persistent excess shedding, which may be a symptom of an underlying medical disorder.
- See your doctor if a scalp infection is suspected. Infection can lead to permanent hair loss.
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Copyright © 2008 Medletter Associates, LLC
Content excerpted from Johns Hopkins Symptoms and Remedies: The Complete Home Medical Reference.