A: The main studies by Merck looked at men between the ages of 18 and 41. The five year data (which, in my view, is most important) showed that 48% of men had an increase in hair growth and 42% had no change over baseline. Thus a full 90% held on to their hair or had more over a 5-year period. This compares very favorably to the placebo group where 75% lost hair over the 5-year period.

I think the most interesting question relates to the 10% who continued to lose hair in the treated group. Did these men lose hair at a slower rate than the non-treated group? Based on the action of finasteride on blocking DHT and DHT’s central role in causing male pattern hair loss, it is reasonable to assume that even these “non-responders” did have some benefit from the drug, albeit small. If half of those on the medication continued to lose hair did so at a rate slower than the placebo group, then 95% of patients actually benefited from the medication to some degree – an extraordinarily high success rate, in my opinion.

A: The majority of women present with diffuse hair loss (i.e. thinning all over) rather than the patterned hair loss seen in men (where the hair is localized to the front and top of the scalp).

Diffuse thinning presents two problems for a potential hair transplant candidate.

The first is that there is no permanent area where the hair can be taken from. If hair is taken from an area that is thinning, the transplanted hair will continue to thin after the procedure, since moving it doesn’t make it more permanent.

The second problem is that since the areas to be transplanted are thin, rather than completely bald, the existing hair in the area of the hair transplant is at some risk to shedding as a result of the procedure.

When women have a more defined pattern (i.e. more localized thinning on the front part of the scalp with a stable back and sides), they can make excellent candidates for surgery. This pattern occurs in about 20% of women. A small percentage of men have diffuse thinning and are, therefore, poor candidates for a hair restoration surgery as well.

A: You’re referring to Hair DX (hairdx.com), which costs about $150 and came to market in January of 2008 as the first test for androgenetic alopecia, aka male pattern baldness.

The test screens for variations in the androgen receptor gene on the X chromosome, the gene that is associated with male pattern hair loss. The purpose of the test is to identify persons at increased risk of developing hair loss before it is clinically apparent – so that medical intervention can be started early, when it is most effective.

It is important to realize that, at this point, there is just an association with this gene and hair loss; the cause and effect has not been proven and the association is not anywhere near 100%. A danger is that patients may overreact to the relatively incomplete information that the test provides. It is best to have the test performed under a doctor’s supervision, so that it can be put in the context of other information that the physician gleans through a careful history, physical and a densitometry hair evaluation. As of this posting, genetic testing for hair loss is not permitted in New York State.

A: If the texture alone has changed there is nothing you can do except to wait. The texture should improve over time even though it has already been 18 months.

If there are signs of genetic hair loss (i.e. male pattern alopecia), then finasteride should be considered.

A: Diffuse hair loss, more common in women, can be the result of a number of underlying medical conditions and therefore it usually requires an extended medical evaluation. We charge $350 for this evaluation.

If you are a male or female with obvious diffuse thinning from androgenetic alopecia (common baldness), or if you have patterned hair loss where the diagnosis is straightforward, the fee is $125.