Sildenafil effects on sexual function in asymptomatic volunteers: a controlled study.

In a naturalistic setting, sildenafil may affect quality, satisfaction, and the desire for intercourse in young asymptomatic men. Healthy men 21 years old or older having sex with a steady female partner for at least 6 months and intercourse frequency of at least twice a week were eligible. Subjects received 4 capsules of sildenafil powder 50 mg to take home for one 2-week period, to use one hour before sexual activity. For a second 2-week period, they received 4 identical placebo capsules. Ten subjects aged 22 to 34 were studied. The effects found in this study were small and of borderline statistical significance. The findings may be analogous to those with antidepressants, where major effects are seen only in clinically depressed patients, however, normal volunteers have subtle and difficult-to-measure effects.