Efficacy and safety of oral sildenafil (Viagra) in men with erectile dysfunction caused spinal cord injury

Objective: To evaluate the efficacy and safety of 50-mg doses of sildenafil during a 28-day period in patients with erectile dysfunction caused by spinal cord injury (cord level range, T6 through L5). Background: Sildenafil is an orally active, potent, and selective inhibitor of phosphodiesterase type 5, an important regulator of cyclic guanosine monophosphate in the human corpus cavernosum. Methods: To be included in this double-blind, placebo-controlled study, all patients had to be able to achieve at least a partial reflexogenic erectile response to penile vibratory stimulation. The study utilized a single triangular sequential trial design. A total of 27 patients were randomized to receive 50 mg of sildenafil or placebo, taken orally as required (not more than once daily) approximately I hour before sexual activity. Results: After 28 days of treatment, nine of 12 patients (75%) on sildenafil and one of 14 patients (7%) on placebo reported that treatment had improved their erections (p = 0.0043). Furthermore, eight of 12 patients (67%) on sildenafil and two of 13 patients (15%) on placebo indicated that they wished to continue treatment (p = 0.018). A significant improvement in satisfaction with their sex life was reported by patients taking sildenafil (p = 0.012). No patients discontinued treatment due to adverse events. Conclusion: Oral sildenafil, taken as required (not more than once daily), significantly improves the quality of erections and satisfaction with sex life in men with erectile dysfunction caused by a spinal cord injury between T6 and L5.