Most of my patients come to see me about problems with their skin, but many of them bring up concerns about their hair during their visits. By far the most frequent hair problem I encounter is hair thinning. It may be surprising to know that I hear about this from women almost as frequently as I hear about it from men. Although there are no magical cures, in many cases there are treatments that can help. To choose the appropriate one, it's important first to identify the cause of the hair loss.

The most common cause of hair loss in men and women is called androgenetic alopecia. This type of hair loss is inherited, and may be related to levels of androgens. Men with androgenetic alopecia develop a receding hair line at the temples along with thinning of hair on the crown of the scalp; while women develop thinning of the hair over the central scalp and usually have normal hair thickness at the periphery.

Another common type of hair loss is telogen effluvium, which occurs when the growth cycles of many hairs become synchronized, and more hair than usual falls out at once. It can be caused by abrupt shifts in hormonal status, such as from starting or stopping oral contraceptives, after pregnancy or after a serious illness or hospitalization.

Telogen effluvium will often resolve on its own after about six months. Androgentic alopecia, on the other hand, inevitably progresses unless it is treated. Hair transplantation is a good option for some people. For patients who prefer to avoid surgery, there are effective medications, and research is ongoing into new treatment options. Topical minoxidil, or Rogaine, can prevent progression of hair loss for many people, and can produce regrowth of hair in both men and women. It takes some time, though, and consistent use for six to 12 months may be needed in order to see a benefit. When it does help, it is important to continue using minoxidil, or the hairs that regrew will be lost again. Minoxidil comes in two strengths: 2 percent and 5 percent. The higher concentration may produce results a little more quickly, although it doesn't ultimately result in more growth of hair on the scalp and may occasionally lead to hair growth on the face.

Finasteride or Propecia is a pill that can also promote regrowth of hair over time, and it can be used in combination with minoxidil. Since this medication blocks androgens, it can cause birth defects if taken during pregnancy and it is approved by the FDA only for use in men.

New research is focusing on potential light treatments for hair loss. Lasers have been used successfully for years to remove hair, and now the focus is shifting to light therapies to regrow hair. One device, the HairMax comb, was approved by the FDA in February for the treatment of male pattern hair loss. This comb, which emits red light, is unlikely to produce more than a modest increase in hair density, and it certainly cannot replace the use of minoxidil and finasteride. However, studies of higher energy light based devices are in progress, and may provide better treatments some day.

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