Objective Double-Blind Evaluation of Erectile Function with Intracorporeal Papaverine in Combination with Phentolamine and/or Prostaglandin E1

Abstract

We performed a double-blind, crossover study using objective measurements to compare maximum rigidity and duration of erections with papaverine hydrochloride in combination with phentolamine mesylate and/or prostaglandin E1. The rationale for the protocol was to combine a smooth muscle relaxant (papaverine) with either or both vasodilating agents (phentolamine and prostaglandin E1) commonly used for injection therapy. The 7 volunteer patients with organic impotence documented by abnormal nocturnal penile tumescence testing were injected with 0.5 to 1.0 ml. papaverine (30 mg./ml.) in combination with phentolamine (0.5 mg./ml.) and/or prostaglandin E1 (5 μg./ml.). Each patient received 2 injections on each of 2 testing dates; injection 2 was given after tumescence resulting from injection 1 had subsided completely. The medications were given in a randomized, counterbalanced order following double-blind procedures. Patients evaluated the erections subjectively. In addition, the RigiScan^* device was used to measure maximum rigidity and duration of erections.