Erectile dysfunction is defined as inability to achieve or maintain penile erection sufficient for sexual satisfaction. It is a serious problem that increases by age. The physiology of penile erection depends mainly on nitric oxide release.

Compare the efficacy and safety of oral sildenafil 50 mg alone or in combination with l-arginine 3 g/day orally on the treatment of erectile dysfunction.

Randomized controlled study with two parallel groups of erectile dysfunction patients; One group received sildenafil 50 mg every other day, while the other group received a combination of sildenafil (every other day)/l-arginine on a daily base. Efficacy was assessed using International Index of Erectile Function-5 score at the baseline and after 8 weeks. Side effects were evaluated across the two groups.

The mean age was 56.3 ± 5 and 56.2 ± 4.4 years in sildenafil and combination groups, respectively. International Index of Erectile Function-5 score was comparable between the two groups at the baseline (p value 0.44). International Index of Erectile Function-5 score was improved from 15.3 ± 2.5 at baseline to 19.2 ± 2.3 after treatment, and this was statistically significant with p value <0.0001. The score was slightly better in combination group in which the average International Index of Erectile Function-5 score was (19.8 ± 2.2) vs. (18.5 ± 2.3) in sildenafil group with p value 0.05. Side effects were more or less the same between the two groups except for gastritis which was more common on combination group.

Adding l-arginine to sildenafil demonstrated more efficacy than sildenafil alone for treatment of erectile dysfunction patients.

Andrology. 2019 Jul 02 [Epub ahead of print]

L M El-Wakeel, F A Fouad, M D Saleem, M Saber-Khalaf

Faculty of Pharmacy, Ain Shams University, Cairo, Egypt., Department of Urology, Sohag University Hospital, Sohag University, Sohag, Egypt.