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Phosphodiesterase Type 5 Inhibitors for Penile Rehabilitation Post Radical Prostatectomy: A Review of Clinical Effectiveness and Guidelines

Last updated: August 24, 2017
Project Number: RC0915-000
Product Line: Rapid Response
Research Type: Drug
Report Type: Summary with Critical Appraisal
Result type: Report


  1. What is the clinical effectiveness of phosphodiesterase type 5 inhibitors (PDE-5Is) for the treatment of adults requiring penile rehabilitation post radical prostatectomy?
  2. What are the evidence-based guidelines associated with penile rehabilitation post-radical prostatectomy in adults?

Key Message

Evidence from five systematic reviews suggests that phosphodiesterase type 5 inhibitors (PDE-5Is) are more efficacious than placebo or no PDE-5Is for post-radical prostatectomy penile rehabilitation. There is either limited or conflicting evidence to demonstrate improved efficacy with longer-term versus shorter-term treatment, or with regular dosing compared with on demand dosing. No significant differences were observed for higher versus lower dosages, or for early versus late post-surgical PDE-5I use. No statistically significant differences in efficacy between sildenafil, vardenafil, avanafil or tadalafil were reported. All of the SRs reported significantly more adverse events in the PDE-5I arm than in the placebo arm, regardless of dose, PDE-5I agent, or administration protocol. The side effects were generally described as mild, and included headache, flushing, dyspepsia, and rhinitis. Evidence from a single randomized controlled trial (RCT) demonstrated no significant differences between regular and on demand sildenafil dosing. Evidence from another RCT suggested that tadalafil once daily was more efficacious than both tadalafil on demand and placebo in improving general and drug-assisted erectile function (EF), shortening the length of time to EF recovery, preserving penile length and reducing the absence of morning erections, and improving treatment satisfaction and quality of life. All of the included studies were limited by potentially inadequate treatment durations. The guidelines recommended PDE-5Is to treat ED post-radical prostatectomy, but the strength of the recommendation was not provided, and the recommendations were often based on evidence that was conflicting, dated, or of low-quality.