Sildenafil citrate effects on seminal parameters in male participants with idiopathic infertility; A randomized, double-blind, controlled cross-over clinical trial study

Purpose: Sildenafil is a phosphodiesterase Type 5 inhibitor, which is a powerful and effective therapy for male erectile dysfunction (ED) and enables to restore temporary ED. The aim of this study was to evaluate the effects of sildenafil on seminal parameters in male participants with idiopathic infertility. Materials and Methods: This randomized, double-blind, controlled cross-over clinical trial study was conducted on 79 participants who had been referred to urology clinics in Rasht. Participants were assigned to two Groups A (n = 40), and B (n = 39). In Phase I, participants in Group A received a pill of sildenafil (50 mg) and then received a pill of placebo after the washout period, and participants in Group B received a pill of placebo and then received a pill of sildenafil after the washout period. In Phase II, participants in Group A received a pill of placebo and then received a pill of sildenafil after the washout period; and participants in group B received sildenafil and then received a placebo after the washout period. Results: The mean age of patients was 34 ± 5 years. There was no significant difference in the mean sperm count before receiving the drug in all groups. Sperm count, motility, morphology, pH, viscosity, and liquefaction time of semen did not significantly change after receiving sildenafil in comparison to their corresponding placebo group (P > 0.05). Conclusion: Sildenafil did not change sperm parameters in treating infertile patients; sildenafil also had no positive effect on semen parameters.