Evaluation of side effects of sildenafil in group of young healthy volunteers


We evaluated the safety and side effects of sildenafil in a group of sexually active volunteers younger than 40 years under conditions without sexual stimulation. Single oral dose of 50 mg dildenafil (n = 20) or placebo (n= 20) was randomly administered to 40 sexually active volunteers with the mean age of 26.80 ± 5.29 in sildenafil group and 25.70 ± 4.95 in placebo group. All the subjects were informed about the study, but not about the medicine. The following tests were performed immediately before and 90 minutes after the administration of the medicine: resting heart rate, blood pressure, electrocardiogram, visual acuity, color vision. The subjects were also asked to describe any discomfort or difference. Mann Whitney U test was used for statistical analyses. The only statistically significant difference was between heart rates before and after the administration of the sildenafil (p = 0.02). Color vision, visual acuity tests yielded no differences. The decrease in blood pressure was not significant. The most common side effects were flushing (75% and 0%), headache (50% and 5%), dyspepsia (15% and 5%), unintentional incomplete sexual arousal (15% and 0%) and palpitation (15% and 10%) in groups of sildenafil and placebo, respectively. The only serious side effect requiring medical treatment was arthralgia on the knee in one subject. Although these side effects can be acceptable, the likelihood of these side effects needs to be made clear to potential users of this medication.

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Dündar, M., Koçak, İ., Dündar, S.O. et al. Evaluation of side effects of sildenafil in group of young healthy volunteers. Int Urol Nephrol 32, 705–708 (2001). https://doi.org/10.1023/A:1015056416501

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  • Normal potency
  • Side effect
  • Sildenafil
  • Young volunteer