Priapism: an avoidable complication of pharmacologically induced erection.

Priapism is an alarming complication during treatment of erectile dysfunction with vasoactive drugs, particularly papaverine alone or in combination with phentolamine mesylate. An investigational protocol was designed to identify patients who are more susceptible to priapism after intracavernous injection of papaverine alone or with phentolamine. The protocol was applied in 331 men with impotence of various etiology. The association of a positive response to visual sexual stimulation and penile brachial index of more than 0.8 represented a higher risk for post-injection priapism. We were able to reduce the incidence of this compliance to 1% in the last 101 patients.