Propecia, the new baldness pill: Does it work?

by Alice Buckley McCarthy

On December 22, 1997, the first-ever pill to treat and slow hereditary hair loss in men, known as Propecia,was approved by the FDA. It started to hit drugstores around the country in mid-January 1998, so if you're one of the 40 million U.S. men with hereditary hair loss, there are now two products available to help you grow and keep your hair. Propecia, which requires a doctor's prescription, joins minoxidil--the active ingredient found in Rogaine, which has been available without a prescription since February 1996.

Propecia is actually a drug called finasteride, first developed to shrink enlarged prostates. Researchers noticed it also helped grow hair, so a special lower-dose formulation was developed for hair loss. It is how Propecia works that enthuses doctors familiar with the drug. Propecia interferes with conversion of testosterone to another hormone called dihydro-testosterone (or DHT). DHT reduces hair follicle activity. Over time, follicles sprout thinner hairs until no hair regrows.

Dr. Ken Washenik, director of dermatopharmacology at New York University who was involved in the drug's clinical trials and who uses the drug himself confirms, "Propecia is so impressive because it is the first medication we have that specifically addresses what we think is the primary factor in hair loss. It's the best thing we have so far."

Minoxidil's activity, in contrast, is thought to involve stimulation of hair follicles to become larger and make normal hairs. Indeed, Dr. Howard Baden, professor of dermatology at Harvard Medical School and a practicing dermatologist at Massachusetts General Hospital also believes Propecia's big advantage is how it works. "[Propecia] really interferes with the pathway for hair loss whereas Rogaine tries to overcome it by stimulating hair growth." He adds a cautionary note though. "I don't think that any drug that we use to arrest a process which progresses with time is going to totally abolish the problem. It will probably significantly slow down the process."

In clinical studies, approximately 20% of men taking the one mg. daily dose of Propecia grew moderate to heavy amounts of new hair after one year. Another 30% had less cosmetically apparent growth. These numbers inched up slightly when used for two years. And both Propecia and minoxidil work best in men who are losing hair on the top of their heads (instead of a receding hairline or frontal hair loss). Minoxidil also may lead to new hair production, but results are more variable because of individual inconsistencies in committing to a twice/daily program of applying the solution to the scalp.

But it isn't only Propecia's ability to grow hair that interests some doctors. "I must say I've been impressed with people not continuing to bald," says Dr. Baden. Indeed, Washenik's research showed that about 70% of men in the Propecia study stopped losing the hair they had. So it appears that even if Propecia doesn't help you grow lots of new hair, it's a good bet you'll keep what you have--at least for a while. "Prevention is always better than trying to treat something," says Baden, citing perhaps what will be one of the biggest reasons why men who are just beginning to lose their hair will consider Propecia.

You must be patient, though, and be willing to take the drug once a day indefinitely. It may take three to four months before new hair is noticed. Dr. Washenik says that "you don't notice hair growing in until about six months. I tell most people a year." If you stop taking the drug, all your newly grown hair will fall out over time. The same is true with minoxidil.

Compared with 5% Rogaine, Propecia will be more expensive. You can expect to pay about $45-$49/month for it, compared to $30 for 5% Rogaine. And, insurance companies won't cover it.

Propecia has some potentially unsettling side effects, but both Washenik and Baden downplay their frequency. About 1-2% of Propecia users complain of a reduced sex drive, occasional impotence, and/or a smaller amount of ejaculate, figures "only a half percentage higher than guys who were on placebo," comments Washenik. These side effects disappear when the drug is stopped. And Washenik's research showed that they disappeared in 58% of men who continued to take the drug despite these side effects. Comparatively, minoxidil's side effects most commonly include scalp itch or skin irritation.

Men taking the drug should alert their physicians. A guaranteed effect of taking Propecia is that it will lower PSA, a compound produced by the body in the presence of a prostate cancer or just with increased age. Blood tests checking for PSA levels may be more difficult to interpret as a result. And because it may reduce the volume of ejaculate fluid, researchers will be looking to see if Propecia affects male fertility, although Dr. Washenik states firmly, "there is no evidence that it decreases sperm count. It may decrease the amount of fluid by around 10%, but there is no evidence that it decreases male fertility."

Propecia will share the spotlight for hair loss therapies with minoxidil--a topical solution available in Pharmacia & Upjohn's Rogaine and other generic products. Following hot on Propecia's December approval, the FDA also gave the nod to a stronger 5% Rogaine solution, which, Washenik suggests is "also a step in the right direction".

You may not want to choose between Propecia or minoxidil, though. Dr. Baden believes that "people should use both." Citing animal studies, he comments that there is evidence that "the effectiveness of both is better than one alone and you're attacking the problem in two different directions." Washenik agrees, commenting that "virtually every man I treat for hair loss I have use both...for a period of about a year. By a year, you'll know if you're somebody that is responding. If you're not, then you may just use one to help keep your hair." But taking Propecia more than once per day or applying minoxidil more than twice/day will not lead to more hair growth.

Admitting that hair loss "is not a life-threatening disease, but a life-affecting problem," Dr. Washenik is nevertheless enthused to have a "remarkably safe" medication available that will "help arrest hair loss in the vast majority of people." Baden's advice? "If you can afford it and you're balding and you want to keep your hair, you'd be smart to take [Propecia]".

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