A review of outcomes of an intracavernosal injection therapy programme


John Mulhall, Sidney Kimmel Center for Prostate and Urologic Cancers, 353 East 68th Street New York NY 10065, USA. e-mail: mulhalj1@mskcc.org


Study Type – Therapy (outcomes research)

Level of Evidence 2b

What's known on the subject? and What does the study add?

Intracavernosal injection (ICI) therapy is an important treatment option for erectile dysfunction. However, high discontinuation rates have been reported for ICI therapy, and a risk of priapism has long been a concern. There has never been a large sample study performed with multivariate analysis to characterise outcomes of ICI therapy.

The present paper reviews ICI therapy outcomes in a very large population of men at a tertiary care Sexual Medicine Clinic over 5 years. Multivariate analysis was used to further characterise these outcomes. The present study shows that for a large percentage of our sample of patients, ICI therapy is a successful treatment strategy. And, while discontinuation rates are still high, many of those not continuing ICI therapy achieved success with phosphodiesterase inhibitors. Also, the incidence of priapism was less in the present study than previously reported.


  • • To review the outcomes, adverse events and discontinuation rates of intracavernosal injection (ICI) therapy in men with erectile dysfunction (ED) in a sexual medicine practice over a 5-year period at a tertiary referral centre.
  • • Since 1983, ICI has become a staple therapeutic option and high success rates have been reported. However, priapism is a significant concern and discontinuation rates are estimated to be >50%.


  • • Men presenting with ED who were enrolled in our ICI programme between September 2002 and August 2006 were followed at least annually.
  • • Patient demographic information, agents used, erectile function outcomes and adverse events were recorded.
  • • Failure was defined as the inability to have penetrative sex. Discontinuation was defined as patient declaration of such, failure to attend an annual follow-up visit or failure to call for a repeat prescription.
  • • Multivariable analysis was used to define predictors of failure to respond to ICI therapy, as well as predictors of discontinuation within 36 months of starting ICI in those patients responding.


  • • In all, 1412 patients had complete data and constituted the study population. Most patients were using Trimix and 89% of Trimix users were capable of having sexual intercourse.
  • • Response rates were lower in pelvic radiation and diabetic patients.
  • • However, the discontinuation rate was significant; it was lower in men who had not undergone radical prostatectomy (RP). Of note, many RP patients discontinued ICI because of recovery of natural or phosphodiesterase type 5 inhibitor-assisted erections.


  • • ICI therapy is associated with very high success rates even in men with high comorbidity profiles; however, the discontinuation rates, even in men who had not undergone RP, by the end of the third year are significant.
  • • Of note, the recorded priapism rate was extremely low (0.5%).