Androgenetic alopecia, or male pattern baldness, is the gradual thinning of the hair follicles, which results in hair becoming finer. Eventually, the follicle may be unable to produce hair. Affecting primarily Caucasians, and only present in men, male pattern baldness results in moderate to total hair loss. The risk of developing male pattern baldness increases with age.
Male pattern baldness tends to result in thinning hair along the sides of the head and temple at first. Hair loss is in an M shape pattern. Even with the earliest cases beginning in adolescence, total hair loss is not predictable. A young man who begins losing his hair in his teens may still have hair when he is in his 70s or 80s. Conversely, a male who begins losing his hair in his 20s may lose all his hair by the time he is 40.
Male pattern baldness depends upon the presence of a specialized type of testosterone, dihydrotestosterone. This normal male hormone does not have to be in excess to result in hair loss. Dihydrotestosterone affects hair as it grows, resulting in the production of fewer and shorter hairs. Other individual hairs are weaker and tend to fall out while combing or washing the hair. The hair follicles begin to decrease in diameter. Results vary, but hair grown from smaller hair follicles tends to be lighter in color, and eventually the narrowing follicles stop producing hair.
Genetics play a factor in male pattern baldness that is widely debated. In the early 20th century, the agreed upon theory was that male pattern baldness was inherited through the mother. Therefore, if a man's maternal grandfather had hair loss, that man would suffer hair loss as well. In the 1980s, the scientific community refuted this concept and posited instead that male pattern baldness could be inherited from either the mother or father.
Very rapid hair loss, or hair loss not following the M shape pattern, may be indicative of a different condition, such as hypothyroidism. If one experiences redness or pain in the hair loss areas, he should seek medical advice, as this is not the typical behavior of male pattern baldness and may indicate other medical conditions.
If male pattern baldness is untreated, hair loss is permanent. Treatment is not necessary, but may be cosmetically desirable. Minoxidil applied directly to the scalp can stop hair loss and re-grow hair. The best results tend to occur with those who begin minoxidil at the first signs of hair loss. Minoxidil needs to be consistently applied, or hair growth will stop and loss will begin again.
Finasteride is taken orally and works by inhibiting dihydrotestosterone. It is considered to be more effective than topical minoxidil. As with minoxidil, the medication must be used consistently or hair loss will resume.
Hair transplants are a more aggressive treatment that actually places new follicles of hair in the areas of greatest loss. If successful, these follicles will grow normally. This treatment is usually expensive, and multiple sessions may be required to place enough follicles. Many patients are very happy with the results and find the expense justified. A slight risk of skin infection is associated with this procedure.
For other men, the best way to handle male pattern baldness is simply to shave the head. The shaved look is fashionable and considered by many to be attractive. If the price of medications or hair transplantation is a concern, shaving the head is clearly the least expensive way to address male pattern baldness.