suffering from erectile dysfunction, they did not compare to the ease of orally administered sildenafil citrate, a cardiovascular dilating agent used for patients with angina. British scientists noted its penis-enhancing capabilities when study participants reported erections. Sildenafil citrate, with the proprietary name of Viagra, caught on like wildfire in the late 1990s, even before Sen. Bob Dole became a spokesperson for the drug. But Viagra's benefits may not be limited solely to males: evidence has suggested that it could also increase genital blood flow in females. Since the advent of sildenafil citrate, two other drugs—vardenafil and tadalafil—have also entered the erectile dysfunction arena. In 2000, the FDA approved the first female prosthesis, the EROS clitoral device.
And research continues as physicians work to unravel the secrets to sexuality. Lue, along with Goldstein, already has confirmed the role of arterial flow and relaxed penile smooth muscle in achieving erections. Moreover, at the University of California, Los Angeles, Jacob Rajfer and Louis Ignarro(a Nobel laureate) identified nitric oxide as the principal neurotransmitter for penile erection.
