Objectives: To investigate the pharmacodynamic effects of the combined administration of vardenafil and ethanol on blood pressure and heart rate and to study the mutual pharmacokinetic interaction, safety and tolerability of the combination.
Methods: 12 healthy male subjects aged 18 - 45 years received 3 different single-dose treatments in a randomized, double-blind, placebo-controlled crossover design: 20 mg vardenafil plus 0.5 g/kg ethanol, vardenafil plus placebo and ethanol plus placebo. Heart rate (HR) as well as systolic (SBP) and diastolic blood pressure (DBP) were measured in supine position after 15 min of rest at 0.25, 0.5, 0.75, 1, 1.5, 2, 2.5, 3, 4, 6, 8, 10, 12, 15 and 24 h post dosing using a validated oscillometric sphygmomanometer. Vardenafil, vardenafil metabolite M-1 and ethanol pharmacokinetics were assessed.
Results: There were no statistically significant differences between treatments in DBP and SBP. Significantly higher increases in HR were seen when the combination vardenafil/ethanol and ethanol/placebo treatment, respectively, was compared with vardenafil/placebo treatment. The difference between the 2 treatments including ethanol, however, was not significant. All hemodynamic changes were not clinically relevant. The pharmacokinetics of vardenafil and ethanol were not changed in the treatment "vardenafil + ethanol" compared to the respective treatment with vardenafil and ethanol alone. The most frequently reported adverse events were vasodilation and nasal congestion, well-known side effects of PDE-5 inhibitors such as vardenafil.
Conclusion: Concomitant administration of vardenafil and alcohol was well-tolerated. No clinically relevant pharmacodynamic or pharmacokinetic interactions were detected.