Concurrent Use of Tadalafil and Alfuzosin: Safety Concerns
The combination of tadalafil and alfuzosin is NOT recommended due to increased risk of symptomatic hypotension without additional therapeutic benefit for BPH symptoms. 1, 2
Guideline-Based Recommendation
The American Urological Association provides a Moderate Recommendation (Evidence Level: Grade C) that clinicians should NOT offer the combination of low-dose daily 5mg tadalafil with alpha-blockers for the treatment of LUTS/BPH, as this combination offers no advantages in symptom improvement over either agent alone and specifically increases the risk of symptomatic hypotension. 1, 2
Critical Safety Issues
Hemodynamic Risks
The combination causes additive blood pressure-lowering effects that can lead to symptomatic hypotension, particularly dangerous in patients with cardiovascular disease, those taking antihypertensive medications, or with intravascular volume depletion. 2
While one hemodynamic study in healthy middle-aged men showed tadalafil 20mg with alfuzosin 10mg daily produced a mean maximal decrease in standing systolic blood pressure of only 4.35 mm Hg (not significantly different from placebo), 3 the AUA guidelines prioritize patient safety and real-world clinical outcomes over isolated research results. 2
Notably, tadalafil combined with doxazosin (another alpha-blocker) produced a significantly greater hypotensive effect with 28% of subjects experiencing standing systolic BP <85 mm Hg, 4 highlighting the class-wide concern with alpha-blocker combinations.
Lack of Therapeutic Advantage
The combination has not been shown to offer greater symptom improvement over alpha-blockers or tadalafil alone, making the increased side effect risk unjustifiable. 1, 5
The AUA guidelines explicitly state this combination is "not recommended, particularly given the higher side effect risk." 1
Recommended Clinical Approach
For Patients with Both BPH and ED (Your Patient's Situation)
The preferred approach is to discontinue alfuzosin and switch to tadalafil 5mg once daily, which treats both conditions with a single medication and avoids drug interaction risks. 2
Tadalafil 5mg daily is specifically licensed and recommended for the combination of LUTS/BPH and erectile dysfunction. 1, 6, 7
This approach provides mean IPSS reduction of -5.4 to -5.6 points compared to -3.6 points with placebo. 6, 5
The dose should be taken at approximately the same time every day, without regard to timing of sexual activity. 7
Alternative Approach if Continuing Alpha-Blocker
If alfuzosin must be continued for BPH management:
Use tadalafil "as needed" for erectile dysfunction only (10-20mg taken prior to anticipated sexual activity, maximum once per day). 7
When coadministering tadalafil with an alpha-blocker for ED, patients should be stable on alpha-blocker therapy prior to initiating treatment, and tadalafil should be initiated at the lowest recommended dose. 7
This approach separates the therapeutic goals and may reduce cumulative hemodynamic effects.
Important Contraindications
Concomitant nitrate use is an absolute contraindication for tadalafil due to risk of severe hypotension. 6, 5, 7
Tadalafil is contraindicated in patients with cardiac disease, hypotension, poorly controlled blood pressure, recent stroke (<6 months), or significant hepatic or renal insufficiency. 1
Cardiovascular risk assessment should be performed before prescribing tadalafil. 5
Common Pitfalls to Avoid
Do not assume that research studies showing potential benefits of combination therapy override guideline recommendations—the AUA explicitly reviewed this evidence and determined the risk-benefit ratio is unfavorable. 1, 2
Do not split tadalafil tablets; the entire dose should be taken. 7
Most common adverse effects of tadalafil include headache, flushing, rhinitis, and dyspepsia. 5