The drug is Propecia, and it works by suppressing a hormone that shrinks hair follicles. A Merck study of 1,553 men found 86 percent of those who took Propecia grew more hair or maintained the amount they had.
Actually, the Propecia program is just a one-fifth dose of Proscar, an existing drug used to treat enlarged prostates. And there are some rare (but deliciously ironic) side effects for men in search of lost youth: decreased libido and sexual dysfunction.
Stop taking the pill and those effects fade — hair loss, however, resumes. Stick with it and this miracle pill could leave you all tressed up and no place to go. At least until a new erection pill, also approved by the FDA, hits the shelves sometime in April.