Comparison of Effects following the Intracorporeal Injection of Papaverine and Prostaglandin E1

A study group of 240 impotent men receiving intracorporeal injections were divided into 2 groups: the first group received papaverine (60 mg) and the second prostaglandin E1 (PGE1 20 micrograms). The effect of the drugs was evaluated according to the onset of erection, rigidity and the duration of erection; 136 patients were treated with papaverine and 104 with PGE1. The onset of action in these groups was 6.42 +/- 5.39 vs 10.14 +/- 5.41 min; the rigidity score was 3.37 +/- 0.89 vs 3.60 +/- 1.10 and the duration of erection was 49.56 +/- 62.56 vs 63.60 +/- 44.57 min respectively. There was a significant difference in the onset of action (PGE1 was slower than papaverine) and maintenance of erection (longer with PGE1 than with papaverine). Another group of 17 patients received both papaverine and PGE1. The effects of papaverine were better in 4 cases, worse in 5 and equal to PGE1 in 8. This study indicates that compared with papaverine, treatment with PGE1 produces a slower onset of action, a longer duration of erection and fewer side effects.