Hair Loss - Common Skin Conditions: Skin Health

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Hair loss

Hair loss affects about 50 million men and 30 million women in the United States. Age-related hair loss usually results from hormonal changes and genetic predisposition. In recent years, topical medications and refined techniques in hair transplantation have helped ease the distress that hair loss causes.

A number of factors can cause hair loss, including immune disorders, exposure to toxic chemicals, stress, burns, and various skin disorders. But more commonly, hair loss is caused by aging or an inherited predisposition to premature thinning called androgenic alopecia. Often referred to as male pattern baldness, androgenic alopecia is more common in men because it develops in response to higher androgen levels. In women, a similar condition is called female pattern baldness. It may occur in women before age 40, but is more likely to coincide with menopause.

Treating hair loss with topical medications

Minoxidil (Rogaine), a nonprescription lotion which is applied topically, and finasteride (Proscar, Propecia), a prescription drug taken orally, are the only two medications the FDA has approved to treat hair loss in men. For women, only minoxidil is approved.

Minoxidil increases the anagen, or growth, phase of hair, and returns shrunken hair follicles to a more normal size. In one study, men who used minoxidil for 96 weeks experienced a 30% increase in hair weight, compared with a slight decrease in men who did not use the drug. A more concentrated solution of minoxidil — 5% versus 2% — has been found to be more effective in increasing the number of hairs in studies of men. In women, minoxidil has been shown to promote new hair growth, but there has been no difference between the two concentrations.

Finasteride, a drug also used to treat prostate enlargement in men, lowers levels of dihydrotestosterone, a hormone involved in hair loss, without disrupting testosterone activity. In a study of 1,215 men who used finasteride for two years, two-thirds had significant improvements in hair growth and the remaining third had as much hair as when the study began. On the other hand, finasteride has not been effective in postmenopausal women.

Thus far, only one study has directly compared minoxidil and finasteride, and it found finasteride more effective. For a year, 40 men with androgenic alopecia took finasteride once a day, and 25 men with the condition used a 5% solution of minoxidil twice a day. At the end of the study, 80% of the finasteride group and 52% of the minoxidil group had thicker hair. Because the medications promote hair growth in different ways, some people choose to use both at the same time. However, there's little evidence that simultaneous use results in more or faster growth.

Hair transplants

Decades ago, the results of hair transplants weren't always attractive. Because transplants moved large "plugs" of hair to thinning, balding areas, the effect often was artificial-looking. Today, refinements in hair transplantation techniques offer a much more natural appearance.

To achieve natural-looking transplants and minimize scarring in the area from which hair has been transplanted, surgeons no longer "punch" pieces of hair-bearing skin from the back of the head. Instead, they cut a small strip of skin from the back of the head, which then is dissected into tiny sections. These micrografts and minigrafts contain as few as one to five hairs. Minigrafts and micrografts provide a natural look around the hairline, but larger grafts can be used behind the hairline to achieve greater density.

Surgeons may choose among several grafting techniques. Needles and blades commonly are used to create the small slits or holes into which the grafts are placed. Sometimes lasers are used. While lasers may result in less bleeding and scarring, regrowth of the transplanted hair may be slower than with more traditional methods. Automated grafting devices that resemble a ballpoint pen with a retractable needle may be used, too. On average, it takes about four hours to transplant 1,000 grafts by hand. But one of the automated devices has been clocked at 38 grafts per minute. Despite their speed, these automated devices may be more expensive to use because they have to be replaced more often than needles and blades, and results with fine hair may not be as good as with coarse hair.

Surgeons perform graft procedures on an outpatient basis with local anesthesia. Bandages can be removed the next day, and most people can resume their everyday activities, with the exception of strenuous exercise. It takes a week to 10 days for scabs or crusting to heal, but many people feel comfortable going out in public wearing a hat or scarf three to five days after the transplant. The transplanted hair begins to grow within three to six months. Within ten to twelve months, most people can expect to see their transplant reach its maximum density.

Most hair transplants will not be completed in one session. Two or three sessions are often needed, depending on the desired result, and they should be spaced about four months apart so the scalp heals adequately between surgeries.

Other hair-restoration techniques

A less common procedure is called skin flap surgery. A section of scalp with healthy hair is cut and moved with one end still attached to maintain blood supply. Essentially, it replaces a piece of bald scalp with a piece that has growing hair. New hair grows and covers the scars.

Another technique, scalp reduction surgery, reduces the size of bald spots at the crown. In this procedure, the surgeon cuts out the hairless area of skin, stretches the scalp, and then sutures it so the areas that are covered with hair will meet. Sometimes physicians combine scalp reduction surgery with the use of scalp extenders or tissue expanders that stretch areas of skin, which is then excised, further reducing the size of the bald area. Physicians also can use these techniques along with grafts or topical minoxidil. Some procedures may require general anesthesia. You can determine which approach is best for you by consulting a dermatologic surgeon.

Last updated:	July 20, 2007