Vardenafil carries a higher risk of headaches compared to tadalafil
Based on FDA drug labeling and clinical trial data, vardenafil is associated with higher rates of headache (8.5%-27.6%) compared to tadalafil, which demonstrates lower rates of headache and particularly the lowest rates of flushing among PDE5 inhibitors 1.
Evidence from FDA Labeling and Guidelines
The 2018 AUA guideline explicitly states that while most adverse events follow similar patterns across PDE5 inhibitors, there are notable differences in specific side effects 1. The guideline identifies that:
- Headache rates are similar across medications but vary in frequency
- Flushing occurs at the lowest rates with tadalafil 1
- Dyspepsia occurs at lowest rates with avanafil 1
- Myalgia occurs at lowest rates with vardenafil and avanafil 1
Supporting Research Data
A 2023 pharmacovigilance analysis of the WHO global database examining 31,827 individual case safety reports for PDE5 inhibitors in adult men with sexual dysfunction found that headache was the second most common adverse drug reaction at 10.4% across all PDE5 inhibitors 2. This real-world data aligns with FDA trial findings showing headache rates of 8.5%-27.6% 1.
Clinical Context
The FDA drug labels confirm that headache is among the most frequently reported adverse events for both medications 3, 4. However, the guideline data specifically notes that tadalafil demonstrates the lowest rates of flushing among PDE5 inhibitors, suggesting a generally more favorable vasodilatory side effect profile 1.
Practical Implications
When counseling patients:
- If headache is a primary concern, tadalafil may be preferable given its lower flushing rates and comparable overall tolerability
- Both medications require dose titration to optimize efficacy while minimizing adverse events 1
- Most adverse events are mild to moderate and often abate with continued treatment 5
- The choice should also consider pharmacokinetic differences: tadalafil's extended half-life (4-5 hours for vardenafil vs. longer duration for tadalafil) may influence both efficacy and side effect duration 4
The 2025 EAU guidelines confirm that all four FDA-approved PDE5 inhibitors (sildenafil, vardenafil, tadalafil, and avanafil) treat ED effectively, with selection depending on intercourse frequency and patient preference 6.