Comparative study of papaverine plus phentolamine versus prostaglandin E1 in erectile dysfunction.

Abstract

We compared the efficacy and short-term adverse effects of 1 ml. 30 mg./ml. papaverine plus 0.5 mg./ml. phentolamine versus 1 ml. 30 micrograms./ml. prostaglandin E1 in patients undergoing pharmacological erection testing. A total of 60 patients (mean age 58 years) with a history of sexual erectile dysfunction longer than 6 months was randomly classified into 6 groups to be tested 1 week apart with the 2 solutions and with placebo to evaluate erection response and short-term adverse effects. Of the patients tested with papaverine plus phentolamine 54% responded with erections adequate for penetration, compared to 50% of those tested with prostaglandin E1 (p > 0.05). Prolonged erection occurred in 18% of patients tested with papaverine plus phentolamine and 15% of those tested with prostaglandin E1 (p > 0.05). Pain was reported by 15 and 35% of patients, respectively (p < 0.05). One ml. 30 mg./ml. papaverine plus 0.5 mg./ml. phentolamine has the same efficacy and equal prolonged erection rate as 1 ml. 30 micrograms./ml. prostaglandin E1 but the latter agent induces significantly more pain.