Alopecia, or excessive hair loss, is a common problem among both men and women, and it can have a considerable negative impact on the body image and emotional wellbeing of affected individuals.
Hair loss can be due to transient factors, such as high fever, acute illness, childbirth, endocrine disorder or certain medications. Hair regrowth often resumes naturally within a few months after the underlying factor subsides.
The most common form of hair loss in adults — known as male pattern or female pattern hair loss, or androgenetic alopecia — is genetically determined. It can start in the 20s in some individuals and occurs more frequently with increasing age: It affects up to 80 percent of men and 55 percent of women by the eighth decade of life.
In women with female pattern hair loss, the hair becomes thinner all over the head, but the hairline (the area along the forehead where hair starts growing) usually does not recede. In contrast, men with male pattern hair loss experience a progressively receding hairline that forms a characteristic “M” shape, and their hair also thins at the crown (near the top of the head), often leading to partial or complete baldness.
Despite the plethora of hair loss products on the market, only two drugs have been approved by the Food and Drug Administration for this condition: topical minoxidil (ROGAINE, THEROXIDIL) and oral finasteride (PROPECIA). These medications are approved for one type of hair loss: androgenetic alopecia involving the crown area of the scalp. These drugs do not reverse hair loss completely; they can stimulate hair growth in some (but not all) people. Currently, no medications are available for treating a receding hairline.
Minoxidil is a topical over the- counter medication that is available in 2-percent and 5-percent concentrations for both men and women. The drug comes in liquid and foam forms that are applied to the scalp once or twice daily.
Studies showed that some increased hair growth occurred in 40 to 60 percent of minoxidil users, resulting in an average increase in hair count of only 8 to 12 percent.
Patients may experience temporary hair shedding in the first four to six weeks of minoxidil therapy. The hair starts to grow slowly after this stage. Therefore, the effectiveness of minoxidil treatment should be assessed at least six months after initiation of therapy to determine whether it works. If minoxidil works, then it needs to be used continually in order to preserve any new hair growth. If the drug is discontinued, the new hair that grew due to minoxidil will fall out, usually within three months.
Scalp irritation and allergic reactions, including dryness, scaling, itching or redness, are the common side effects associated with minoxidil. Another possible side effect for this drug is hypertrichosis: unwanted hair growth on the face or neck. Hypertrichosis can be reduced by only applying the drug directly to the scalp in a thin layer well before bedtime or by using a head covering to limit unwanted spreading of the drug. Severe hair growth on the face and limbs has been reported in women who have used the 5-percent concentration of minoxidil products. Absorption of the drug from the scalp into the bloodstream may have played a role in such cases. The hypertrichosis resolved after stopping the drug.
Minoxidil also uncommonly can cause chest pain, rapid heartbeat, dizziness and swelling of the hands or feet. Minoxidil should not be used in women who are pregnant or nursing because it can harm the fetus or infant. The drug also can cause significant toxicity if taken accidently by children.
Only the 1-milligram (mg) tablet of the prescription drug finasteride is approved by the FDA for treatment of hair loss in men. It stimulates hair growth by blocking the conversion of testosterone to another male hormone that thins the hair and causes the prostate to grow. Evidence from clinical trials in men aged 18 to 41 with mild to moderate degrees of male pattern hair loss show that the drug increases hair growth in nearly half of users after one year of treatment compared with only 7 percent of men receiving a placebo. Similar to minoxidil, any hair that grows due to finasteride is shed after the drug is discontinued.
In contrast to studies in men, the single randomized clinical trial testing finasteride in post-menopausal women with androgenetic alopecia showed that the drug offers no benefit in increased hair growth over a one-year period. Nevertheless, some doctors still prescribe it to women (a practice called off-label prescribing). Pregnant women in particular should not handle crushed or broken finasteride tablets because the drug is harmful to the male fetus.
Our decision was based on a federally funded study that found that the 5-mg form of this drug (PROSCAR), which is approved for treatment of benign prostate enlargement, increases the risk of a serious form of prostate cancer known as highgrade cancer.
Finasteride use at both the 1-mg dose for male pattern hair loss in otherwise healthy men and at the 5-mg dose in men with prostate enlargement has been associated with diminished sex drive and sexual dysfunction, which may persist for months or years after the drug is discontinued.
What You Can Do
For healthy hair, avoid stress and eat healthy, nutritious food with adequate amounts of proteins, vitamins, iron and zinc. Vitamin and mineral supplements are needed only if you have a deficiency.
If you develop hair loss, consult your doctor to determine whether it is secondary to an underlying condition that needs to be identified and treated or due to androgenetic alopecia.
Whether you are a man or a woman, do not take any medication other than minoxidil for androgenetic alopecia. Minoxidil may not work for everyone; if it works for you, then you will need to take it indefinitely in order to preserve any gained hair growth. If it does not work after six or more months of therapy, you should discontinue it.
Do not take finasteride for hair loss (or for any other reason) because it can increase the risk of high-grade prostate cancer and cause significant sexual side effects in men and because it is not effective in women.