A pilot study of the role of intracavernous injection of vasoactive intestinal peptide (VIP) and phentolamine mesylate in the treatment of erectile dysfunction.

Twenty men with chronic impotence with a mean age of 46 years (range 26-63 y) were treated with self administration of 0.35 ml of Vasopotin 1 and 2, a combination of 30 mg Vasoactive Intestinal Peptide (VIP) and either 1.0 or 2.0 mg Phentolamine Mesylate. All patient were assessed using a standard protocol which included history and examination, vibratory penile biothesiometry, colour flow duplex Doppler ultrasonography and where indicated, Rigiscan nocturnal penile tumescence testing, dynamic infusion cavernosometry and cavernosography (DICC) and angiography. Impotence was classified as psychogenic in six patients, arteriogenic in nine patients, neurogenic in two patients and cavernosal venous leakage in three patients. A total of 60 injections was given. After sexual stimulation, an erection of sufficient rigidity for intercourse occurred in six patients with psychogenic impotence, seven of the nine patients with arteriogenic impotence, two patients with neurogenic impotence and one of three patients with cavernosal venous leakage. No patients experienced priapism, two patients complained of postinjection penile pain and three patients experienced transient facial flushing. Intracavernous self injection of Vasopotin appears to be a useful treatment for erectile dysfunction.