December 1997, Volume 9, Issue 4, Pages 193 – 196

Review Article

Review Article – Does natural erectile function improve following intracavernous injections of vasoactive drugs? ID Sharlip1 Pan Pacific Urology, San Francisco, California, USA     1Correspondence: Dr ID Sharlip, 2100 Webster Street, Suite 309, San Francisco, CA 94115, USA.

Keywords

intracavernous injection;   vasoactive drugs;   prostaglandin

Abstract

Improvement in natural erections has been reported in approximately 9% of impotent men using intracavernous injections of vasoactive drugs for erection induction. The mechanisms which may account for this improvement are psychogenic, improved cavernous hemodynamics, prostaglandin-induced angiogenesis, improved cavernous oxygenation, cavernous smooth muscle hypertrophy and/or normal episodic fluctuations in erectile function. A review of the basic science literature on this subject reveals several theoretical explanations for this phenomenon but a review of the clinical literature reveals little convincing evidence that physiologic and/or pharmacologic factors are responsible for improvement in natural erections with intracavernous injection therapy. Furthermore, the prevalence of a placebo effect from impotence therapy exceeds the reported rate of improvement in natural or spontaneous erections. The most plausible explanations for spontaneous improvement in erections during or after intracavernous injection therapy are psychogenic and episodic variations in erectile function, rather than physiologic or pharmacologic factors. However, intracavernous injection therapy started soon after radical prostatectomy may have a protective effect in preserving normal cavernous physiology and erectile function in men being treated for prostate cancer.

Received 10 April 1997; Accepted 10 April 1997

^© Macmillan Publishers Ltd 1997