Effectiveness

New Study Proves Viagra Effective For Male Impotence

Viagra, approved by the U.S. Food and Drug Administration, is proven to be an effective, well-tolerated treatment for men with erectile dysfunction.

The drug works by increasing the penile response to sexual stimulation.

Irwin Goldstein of Boston University Medical Center and his colleagues in the Sildenafil Study Group evaluated the efficacy and safety of Viagra used as needed in two sequential double-blind studies of men with erectile dysfunction of organic, psychogenic or mixed causes.

In a 24-week dose-response study, 532 men were treated with 25, 50, or 100 mg or placebo. In a 12-week, flexible dose-escalation study, 329 different men were treated with Viagra or placebo, with dose escalation to 100 mg based on efficacy and tolerance. After this dose-escalation study, 225 of the 329 men entered a 32-week, open-label extension study, where the researchers assessed efficacy according to the International Index of Erectile Function, a patient log, and a global-efficacy question.

In the dose-response study, Viagra helped achieve erections in all the men taking the 100 mg dose. In the last four weeks of treatment in the dose-escalation study, 69 percent of all attempts at sexual intercourse were successful for the men taking Viagra compared with 22 percent for those receiving placebo. The mean numbers of successful attempts per month were 5.9 for the men receiving sildenafil and 1.5 for those receiving placebo.