Can a man taking tadalafil for benign prostatic hyperplasia also use avanafil for erectile dysfunction?

Can a Man Taking Tadalafil for BPH Also Use Avanafil for ED?

No, a man taking tadalafil 5 mg daily for benign prostatic hyperplasia should not add avanafil (or any other PDE5 inhibitor) for erectile dysfunction—instead, the existing tadalafil regimen already treats both conditions simultaneously, and adding a second PDE5 inhibitor increases the risk of severe hypotension and other adverse effects without providing additional benefit. 1

Why This Combination Is Not Recommended

• The American College of Physicians explicitly recommends optimizing the dose of a single PDE5 inhibitor rather than adding a second one for patients with erectile dysfunction and BPH, due to the increased risk of severe hypotension and other adverse effects 1
• Tadalafil 5 mg once daily is FDA-approved to treat both BPH/LUTS and erectile dysfunction simultaneously, making a second PDE5 inhibitor redundant 1, 2
• Combining two PDE5 inhibitors creates additive vasodilatory effects that significantly increase the risk of symptomatic hypotension, dizziness, headache, and cardiovascular complications 2

The Correct Management Strategy

If erectile function remains suboptimal on tadalafil 5 mg daily for BPH, the solution is NOT to add avanafil—instead, verify that an adequate trial has been completed and address modifiable factors before considering any changes. 1

Step 1: Verify an Adequate Trial

• Confirm the patient has completed at least 5 separate attempts at sexual activity while on tadalafil 5 mg daily 1
• Ensure adequate sexual stimulation is occurring—PDE5 inhibitors require arousal to work and do not create spontaneous erections 1
• Check that the patient is avoiding large or fatty meals when planning sexual activity, as food can reduce efficacy 1
• Verify limited alcohol consumption—heavy alcohol use impairs erectile function independent of medication 1

Step 2: Address Modifiable Factors Before Any Change

• Screen for testosterone deficiency: Check total testosterone, free testosterone, and SHBG—men with testosterone <300 ng/dL respond less robustly to PDE5 inhibitors alone, and combining tadalafil with testosterone therapy may be more effective than tadalafil alone 1
• Review concomitant medications: Identify drugs that worsen erectile dysfunction (antihypertensives, antidepressants, opioids) and consider alternatives if possible 1
• Evaluate psychological factors: Screen for depression, anxiety, and relationship conflict, as these significantly impact treatment response 1
• Assess cardiovascular fitness: Verify the patient can walk 1 mile in 20 minutes or climb 2 flights of stairs—if unable, refer to cardiology before escalating therapy 1

Step 3: If Tadalafil 5 mg Daily Remains Inadequate After Addressing All Factors

The correct approach is to switch to as-needed tadalafil 10-20 mg (taken 30 minutes before sexual activity) rather than adding avanafil. 1

• As-needed tadalafil dosing provides higher peak drug levels during sexual activity compared to the steady-state levels achieved with 5 mg daily 1
• Tadalafil remains effective for up to 36 hours, allowing spontaneous sexual activity without precise timing 1
• If switching to as-needed dosing, discontinue the daily 5 mg dose and use tadalafil 10-20 mg as needed, but recognize that BPH symptoms may worsen without daily dosing 1

Step 4: Alternative Strategy for Dual Indication Management

If BPH symptoms are adequately controlled and erectile dysfunction is the primary concern, consider switching from tadalafil 5 mg daily to an alpha-blocker (tamsulosin or alfuzosin) for BPH, then using as-needed avanafil or vardenafil for ED. 1, 2

• This approach separates the treatment of the two conditions and allows higher-dose, as-needed PDE5 inhibitor therapy for erectile dysfunction 1
• However, the American Urological Association recommends against combining tadalafil with alpha-blockers, as this combination offers no additional symptom benefit over either agent alone and increases side effects 3, 2

Critical Safety Considerations

• Verify absolute absence of nitrate use in any form before prescribing any PDE5 inhibitor—the combination can cause potentially fatal hypotension 1, 2
• Assess cardiovascular risk before any PDE5 inhibitor therapy: patients with unstable angina, uncontrolled hypertension, recent MI, NYHA Class II-IV heart failure, or severe valvular disease should defer ED treatment until cardiac condition is stabilized 1
• If the patient requires emergency nitrate administration while on tadalafil, wait 48 hours after the last tadalafil dose before giving nitrates, under close medical supervision 1

Common Pitfall to Avoid

The most critical error is assuming that tadalafil 5 mg daily is insufficient for erectile dysfunction without completing an adequate trial and addressing modifiable factors. 1 Many apparent failures are due to incorrect use—lack of sexual stimulation, improper timing, heavy alcohol use, or undiagnosed testosterone deficiency—rather than true medication inefficacy. 1