Millions of American men are about to get a treatment revolution for impotence: new pills that promise to restore sexual function without the discomfort and embarrassment of traditional therapies.
The first oral medicine for impotence _ a drug that can cause erections within 20 minutes of swallowing the pill _ could be sold by April, doctors said Monday.
"Some of these drugs are very potent, very unique," said Dr. Harin Padma-Nathan of the University of Southern California and director of the Male Clinic in Santa Monica, Calif. "We could combine them in a cocktail . . . some to work in the brain and some to work locally, for the best effect."
Between 10-million and 20-million American men suffer impotence at some point. The condition is treatable, but penile implants, vacuum devices and injections can be painful or inconvenient.
Now three experimental pills promise help:
+ Pfizer Inc.'s Viagra, or sildenafil, blocks an enzyme found mainly in the penis that breaks down a chemical produced during sexual stimulation. The longer that chemical stays around, the better chance of an erection.
In clinical studies of several thousand men, Viagra helped about 80 percent, said Padma-Nathan, who helped test all three drugs. Unlike injection drugs, Viagra doesn't cause erections unless the man is sexually stimulated.
+ Tap Pharmaceuticals' apomorphine works completely in the brain, Padma-Nathan said. Apomorphine affects chemicals in the brain region associated with initiating erections. It is 70-percent effective in the psychologically impotent.
+ Vasomax is an oral version of an injection drug that dilates penile blood vessels. Trials show it can help about 40 percent of men with moderate impotence.