The enhancement of vaginal vasocongestion by sildenafil in healthy premenopausal women

Objective: This study examined the effect of a single oral dose of sildenafil citrate (Viagra(R) Pfizer, Inc., New York, NY) on vaginal vasocongestion and subjective sexual arousal in healthy premenopausal women. Methods: Twelve women without sexual dysfunction were randomly assigned to receive either a single oral 50 mg dose of sildenafil or matching placebo in a first session and the alternate medication in a second session. Subjective measures of sexual arousal were assessed after participants had been exposed to erotic stimulus conditions. Vaginal vasocongestion was recorded continuously during baseline, neutral, and erotic stimulus conditions. At the end of each session, subjects were also asked to specify which treatment they suspected they had received. Results: Significant increases in vaginal vasocongestion were found with sildenafil treatment compared with placebo. There were no differences between treatments on subjective sexual arousal experience. Analyses by suspected treatment received found that significantly stronger sexual arousal and vaginal wetness were reported for the treatment that was believed to be sildenafil vs. the treatment that was believed to be placebo. The suspected treatment sequence was incorrect for half of the women. Sildenafil was well tolerated, with no evidence of significant adverse events. Conclusions: Sildenafil was found to be effective in enhancing vaginal engorgement during erotic stimulus conditions in healthy women without sexual dysfunction but was not associated with an effect on subjective sexual arousal.