The most common type of baldness is male pattern baldness (androgenic alopecia). It may begin in the teenage years, and becomes more common as men age. The pattern of hair loss is predictable. The hairline begins to recede at the temple, then the hair at the top of the head thins out. After a period of time, the crown area may become completely bald, leaving hair around the back and on the sides of the head only.

Male baldness affects well over one-half of the adult male population, and is so common that some degree of hair loss is considered normal in adult males. Hair loss is caused by a combination of heredity, hormones, and age. Men with high levels of the hormone DHT (dihydrotesterone) tend to lose their hair at higher rates than those with lover levels. However, heredity plays a large part in determining hair loss, and it is due to a sex-linked characteristic that is passed from parent to child. As a rule, a man can more accurately predict his chances of developing male baldness by looking at his mother's father rather than his own.

There are a variety of treatments for male baldness:

Drugs In January 1990 the U.S. Food and Drug Administration banned the sale of all nonprescription hair-loss products. Two prescription drugs have emerged to treat male baldness:

• Minoxidil (Rogaine) — This is a solution that is applied directly to the scalp to stimulate the hair follicles. It slows hair loss for some men, while growing new hair in others.
• Finasteride (Propecia) — This is a pill that inhibits the production of DHT. With this treatment, men are likely to have slower hair loss than actual new hair growth. It appears to be somewhat more effective than minoxidil.

The previous degree of hair loss returns when either of these treatments is stopped.

Hair Transplants In this surgical procedure, plugs of hair are taken from areas where hair is continuing to grow and placed in areas that are bald. Minor scarring can occur in the donor areas and there is a small risk of skin infection. The procedure usually requires multiple sessions and can be very expensive. The results, however, are excellent and permanent.

Prosthetic Hair Replacement Toupees and hairpieces are a third alternative for male baldness. The quality and appearance of toupees has improved over the years, and there are many hairpieces available that mimic the color and texture of real hair.