Viagra for Women?

German drugmaker Boehringer Ingelheim didn't set out to create a Viagra-like drug for women. The company was simply trying to develop a fast-acting antidepressant, one that patients would respond to in a matter of days, not weeks as in most current treatments. By the late 1990s the company had developed a molecule called flibanserin that seemed to relieve stress in rats. But like many promising drugs, it flopped in human trials. Says Dr. Lutz Hilbrich, the company's executive director of general medicine: "We did not see the effect we were expecting."

But what they did see surprised them. Like all companies working on antidepressants, Boehringer surveyed patients in its clinical trial to assess dampening of libido, a well-established side effect. Far from complaining about a drop in sexual desire and arousal, many of the women in the trial reported a surge.