Can the Hair Loss Drug Propecia Safely Reverse Hair Loss?




Like Rogaine (minoxidil), Propecia — also called “finasteride” — is a drug that was developed for another purpose (shrinking noncancerous enlarged prostates) but, by accident, was found to be able to stimulate the growth of hair that had thinned from androgenic alopecia.

But if you are the kind of person who worries about medication side effects and unintended consequences, you need to consider those that come with Propecia.

The good news is it works for a majority of the people who try it — about half stem further loss of hair, while the other half experience new growth. The bad news is women should not use it. In fact, women who could be pregnant should probably not be in the same house with it, owing to a specific and devastating side effect (see “Side effects on women, fetuses and young children,” below).

Propecia works for a majority of those who use it

Because the manufacturer of Propecia, the first brand approved by the U.S. Food and Drug Administration (FDA) to be marketed as a treatment for male pattern baldness, is Merck Pharmaceutical, the most extensive research on efficacy of finasteride is conducted by the company. Merck’s five-year clinical tracking of 279 men on Propecia revealed the following:

  • 42 percent visibly halted hair loss (according to blind assessments of photos by dermatologists)
  • 48 percent visibly regrew hair (according to blind assessments of photos by dermatologists)
  • 66 percent regrew hair, as measured by hair counts

As with minoxidil, use of Propecia needs to be consistent and continuous for it to be and remain effective. Also, its effects are only on hair follicles found on the crown (vertex) of the head, not the forehead or other areas.

How does Propecia work?

The mechanisms for how Propecia works at restoring hair growth are better understood than those for minoxidil. But there still is a bit of uncertainty because the exact mechanisms in hair loss itself are not fully established. Androgenic alopecia is probably caused by excess DHT (dihydrotestosterone), a metabolite of testosterone (i.e., testosterone typically is converted to DHT in some areas, including the scalp). Too much DHT is believed to shrink hair follicles to the point where hair is barely visible. Propecia reduces the conversion of testosterone to DHT by 60-70 percent, which apparently reduces the negative impact of DHT on hair follicle health.
But a question lingers: How comfortable are you with ingesting a prescriptive medication, the mechanisms of which are not fully understood?

There are side effects to Propecia

Every action has a reaction, of course, particularly in the human endocrine system. By reducing the transformation of testosterone to something else, the guy taking Propecia is left with more testosterone.

That’s a good thing, right? Maybe yes, maybe no or maybe it doesn’t matter. As men age, testosterone levels naturally decline (more so with poor lifestyle habits such as overeating, inactivity and excessive consumption of alcohol), so a little extra testosterone might be beneficial. But too much testosterone is associated with impulsivity, aggression, irritability and depression. DHT conversion is important elsewhere in the body, and a deficiency can paradoxically lead to an overexpression of naturally present estrogen (all men have estrogen, in lower proportions than in women). In a small percentage of men, that means enlarged breasts (gynecomastia).

Other side effects seen in a small portion (less than 5 percent) of men using Propecia to address male pattern baldness are:

  • Hypersensitivity (itching and hives, swelling of the lips and face)
  • Testicular pain
  • Increased libido (10 percent in the first months of use)
  • Decreased libido (1 percent throughout its use)
  • Erectile dysfunction
  • Decreased volume of ejaculate

Additionally, men who ask their doctor for a Propecia prescription need also to inform him or her if they have any of the following pre-existing conditions:

  • Liver disease or abnormal liver enzyme tests
  • Prostate cancer
  • Bladder muscle disorder
  • Stricture of the urethra
  • Restricted ability to urinate

Side effects of Propecia on women, fetuses and young children

The only clinical study of Propecia on women was on individuals who were postmenopausal, and the research indicated no beneficial effect from its use. It’s possible to be critical of that finding, since older women may not realize the same results as younger woman with androgenic alopecia.

Why not test it on younger women? Propecia is a teratogen, which means it can cause birth defects. Specifically, exposure of even powder from a broken Propecia tablet to the skin of a pregnant woman can cause abnormalities of the external genitalia of a male fetus. There is further concern that young children similarly exposed may experience adverse affects as well.
Clearly, it’s a risk to be taken seriously.

Can a guy combine Rogaine and Propecia for extra effectiveness?

Many Web sites — particularly those selling hair loss prevention products that include Propecia and minoxidil — advocate use of both products, a double-hit at the scalp from outside and in. The anecdotal claims are that the results are synergistic.

It should be noted that no data exist to support either efficacy or safety claims of this practice.

Cost of Propecia

A four-week supply of Propecia costs approximately $60. Most insurance plans would not cover the cost of this medication for hair loss applications.

To summarize, Propecia will be most effective if you:

  • Are male
  • Do not have certain pre-existing conditions such as problems with the liver, prostate or bladder
  • Are comfortable taking oral medications that have a hormonal effect
  • Are not in the presence of either a woman who is pregnant or younger children, or can assuredly keep the medication isolated from them
  • Are comfortable with the lack of long-term use data (i.e., the product was first approved for marketing as a hair loss treatment in 1997; therefore, there is no research on adverse side effects over many years)