Efficacy and Safety of Tadalafil Once-a-Day versus Tadalafil On-Demand in Patients with Erectile Dysfunction: A Systematic Review and Meta-Analyses

Urol Int. 2017;99(3):343-352. doi: 10.1159/000477496. Epub 2017 Jun 21.


Introduction: To compare the efficacy and safety between tadalafil once-a-day and tadalafil on-demand dosing regimen in patients with ED.

Materials and methods: A systematic search of Medline, Embase, and Cochrane Library was performed to identify all randomized controlled trials (RCTs) that compared tadalafil used a once-a-day with an on-demand dosing regimen for erectile dysfunction. A secondary hand-search was performed in relevant journals, references, and the grey literature. Meta-analyses were performed using Review Manager version 5.3.0.

Results: Six RCTs involving a total of 1,534 patients were included in this review. All studies reported the International Index of Erectile Function-Erectile Function domain score and the results of the meta-analysis showed no difference between the groups. The overall pooled estimated weighted mean differences (WMD) was 0.97 (95% CI -0.37 to 2.32; p = 0.16). Meta-analyses of Sexual Encounter Profile questions 2 and 3 (SEP-2 and SEP-3) showed that the once-a-day dosing regimen was superior to the on-demand regimen with statistical significance. The WMD of SEP-2 and SEP-3 were 10.32 (95% CI 3.16-17.48; p = 0.005) and 11.07 (95% CI 2.57-19.56; p = 0.01), respectively. Both dosing regimens of tadalafil showed similar complication rates. The meta-analyses of adverse events showed no significant differences.

Conclusions: The efficacy rates of tadalafil once-a-day and on-demand were similar. No significant difference in safety was found between the 2 dose regimens of tadalafil.

Keywords: Dosing regimen; Erectile dysfunction; Systematic review; Tadalafil.

Publication types

  • Meta-Analysis
  • Review
  • Systematic Review

MeSH terms

  • Chi-Square Distribution
  • Drug Administration Schedule
  • Erectile Dysfunction / diagnosis
  • Erectile Dysfunction / drug therapy*
  • Erectile Dysfunction / etiology
  • Erectile Dysfunction / physiopathology
  • Humans
  • Male
  • Odds Ratio
  • Penile Erection / drug effects*
  • Phosphodiesterase 5 Inhibitors / administration & dosage*
  • Phosphodiesterase 5 Inhibitors / adverse effects
  • Randomized Controlled Trials as Topic
  • Recovery of Function
  • Risk Factors
  • Tadalafil / administration & dosage*
  • Tadalafil / adverse effects
  • Time Factors
  • Treatment Outcome
  • Urological Agents / administration & dosage*
  • Urological Agents / adverse effects


  • Phosphodiesterase 5 Inhibitors
  • Urological Agents
  • Tadalafil