Rogaine Treatment for Men & Women: The Differences

Rogaine 2% is for women, and Rogaine 5% is for men, but there's more ...

Rogaine originally received FDA approval for Men's Rogaine and Women's Rogaine with a 2 percent minoxidil solution and Men's Rogaine Extra Strength Topical Solution and Men's Rogaine Foam with a stronger 5 percent minoxidil solution for men only. But, many doctors use them for both sexes, so what’s the difference?

"Simply stated," says New York City board-certified dermatologist and hair transplant surgeon Dr. Eric Schweiger, "that’s just how Rogaine currently has the FDA approvals, and it would be very costly and time consuming for them to go through the clinical trials to approve the 5 percent minoxidil solution for women. I use both for women in my practice, depending upon the specific hair loss, sensitivity and scalp situation," he states.

According to the U.S. National Library of Medicine’s National Center for Biotechnology Information, the generic active ingredient minoxidil was approved by the Federal Drug Administration (FDA) for use topically in Rogaine for men’s hair regrowth in 1988, and later, in 1992, the same 2 percent minoxidil formula was approved for women. This identical Rogaine 2 percent minoxidil formula for both men and women was approved in 1996 for over-the-counter sale. The stronger (5 percent minoxidil solution) Men's Rogaine Extra Strength Topical Solution was introduced, tested and FDA-approved for men only in 1997, and in 2006 Men's Rogaine Foam was introduced.

According to Schweiger, another difference in the formulas aside from concentration of the minoxidil hair regrowth ingredient is that the 5 percent solution contains propylene glycol for better skin penetration, which makes the medication more effective, whereas the 2 percent solution is alcohol based. Although both the alcohol- and propylene glycol-based preparations can irritate the scalp, propylene glycol can cause actual allergic reactions in those who are sensitive, which is where evaluating a patient’s skin and scalp carefully becomes important.

Rogaine testing for women

A 2002 clinical trial conducted on men only at the Duke Dermatopharmacology Study Center in Durham, North Carolina, compared the 5 percent minoxidil to results using the 2 percent minoxidil solution. The study showed that men experienced 45 percent more hair regrowth with the stronger solution. Additionally, users of the stronger solution experienced results sooner than did users of the 2 percent one. And although those study results were published in the Journal of the American Academy of Dermatology, according to Dr. Schweiger, preliminary trials on women had not shown any increased effectiveness with the stronger 5 percent minoxidil solution, so the product was never further developed for women.

But a 2004 study by the Cincinnati, Ohio-based Dermatology Research Associates tested 381 women to find out whether the 5 percent minoxidil solution would be more effective in the treatment of female pattern hair loss than the 2 percent minoxidil solution. The study results also were published in the Journal of the American Academy of Dermatology, and it was determined that the 5 percent topical minoxidil group’s hair regrowth results were superior to those in the 2 percent topical minoxidil group. It should be mentioned that both studies were "funded by Pfizer Inc., original maker of Rogaine products.

Is Men's Rogaine Extra Strength Topical Solution too strong for women?

The 2004 study also found an increased occurrence of local irritation and the observation of facial hair growth with 5 percent topical minoxidil that were not experienced in the 2 percent topical minoxidil or the placebo. Schweiger agrees that the stronger concentration can irritate women’s more delicate skin tissues, and therefore he evaluates each patient accordingly. "A small percentage of female patients experience facial hair growth as a side effect of using either Rogaine, which is more common when using the 5 percent solution, but this side effect subsides once the medication is discontinued."

Effective Rogaine usage for both men and women

Dr. Schweiger says, "The most important consideration is that the active hair regrowth ingredient minoxidil, no matter what the concentration, must reach the scalp twice per day in order to be effective. For some women, the foam formula will not be as effective as the liquid formula because it gets caught in the hair and does not reach the scalp." In addition, the stronger 5 percent minoxidil propylene glycol formula is greasier than the 2 percent minoxidil alcohol-based formulation. Because of this, he states, "For patients who complain of the greasiness, we advise minoxidil 5 percent at bedtime and 2 percent in the morning."