Intracavernous chlorpromazine versus phentolamine: a double-blind clinical comparative study

Intracavernous pharmacotherapy is one of the most common treatment modalities of erectile dysfunction (ED). There are different drugs that are used for intracavernous injection including papaverine, phentolamine, prostaglandins E1, phenoxybenzamine, and moxisylate.

The aim of this study is to evaluate the efficacy of chlorpromazine as an intracavernous vasoactive agent alone or with other drugs.

This study was performed on 50 patients presenting to our department complaining of ED. Patients were divided into three groups according to the type of intracavernous drug injected. Group A included 20 patients who received an intracavernous injection of 1 mL bimix (30 mg papaverine + 1 mg phentolamine) followed a week later by intracavernous test dose using a 1 mL mixture of papaverine and chlorpromazine (30 mg papaverine + 2.5 mg chlorpromazine). Group B included 20 patients who received an intracavernous injection of 1 mL trimix (30 mg papaverine + 1 mg phentolamine + 10 microg PGE1). A week later they received another intracavernous test dose using a 1 mL mixture of papaverine, PGE1, and chlorpromazine (30 mg papaverine + 2.5 mg chlorpromazine + 10 microg PGE1). Group C included 10 patients who received various intracavernous injections of chlorpromazine in doses 1 mg, 2 mg, 5 mg, and 10 mg.

There was no significant difference in erection response and erection duration between phentolamine and chlorpromazine. Prolonged erection occurred in two patients of group B and postural hypotension occurred in three patients of group C.

Chlorpromazine can be used as an intracavernous vasoactive agent; it is similar to phentolamine in efficacy and short-term side effect profile.