In clinical studies of mostly white women aged 18-45 years with mild to moderate degrees of hair loss, the following response to 2% minoxidil topical solution was reported: 19% of women reported moderate hair regrowth after using 2% minoxidil topical solution for 8 months (19% had moderate regrowth; 40% had minimal regrowth). This compares with 7% of women reporting moderate hair regrowth after using the placebo, the liquid without minoxidil in it, for 8 months (7% had moderate regrowth; 33% had minimal regrowth).
Anti-androgens. Androgen receptor–blocking drugs such as spironolactone (Aldactone) and finasteride (Propecia) are not approved for the treatment of female pattern hair loss, and there is little reliable evidence that they are effective. However, some case studies suggest that women who don't respond to minoxidil may benefit from the addition of spironolactone. In the relatively uncommon cases where there is an excess of androgen, a clinician may prescribe 100 to 200 milligrams of an androgen receptor–blocking drug daily, together with an oral contraceptive for women of reproductive age. (A woman taking one of these drugs should not become pregnant because they can cause genital abnormalities in a male fetus.) Possible side effects include weight gain, loss of libido, depression, and fatigue.
The other main hair-loss treatment that was recommended by all four dermatologists I interviewed is finasteride, often called by its brand name Propecia. This FDA-approved medication is only available with a prescription, but these days, it’s found as a generic and ordered online after a virtual consultation, through start-ups like Hims, Keeps, and Lemonaid.