The effects of food on the pharmacokinetics of vardenafil were examined in 25 healthy adult males. Single-dose vardenafil 20 mg was administered in a randomized four-way crossover design after an overnight fast (at 8 a.m.), after consumption of a high-fat breakfast (at 8 a.m.), on an empty stomach (at 6 p.m.), and after a typical moderate-fat evening meal (at 6 p.m.). Serial blood samples were analyzed for vardenafil and metabolite (M1) levels. When administered after an overnight fast and after a high-fat breakfast, vardenafil geometric mean Cmax was 17.14 and 14.0 micrograms/L, respectively, and AUC was 66.78 and 67.09 micrograms./h/L, respectively; the median tmax was 1 hour under fasting conditions and 2 hours with consumption of high-fat breakfast. When administered in the evening on an empty stomach and after a moderate-fat meal, vardenafil geometric mean Cmax was 14.22 and 13.04 micrograms/L, respectively, and AUC was 51.97 and 59.12 micrograms.h/L, respectively. The median tmax was 1 hour after fasting or a moderate-fat meal in the evening. All treatments were well tolerated. Thus, while a high-fat meal may alter Cmax slightly and delay the absorption up to 1 hour, a moderate-fat meal has no clinically relevant effect on vardenafil pharmacokinetics. Dosage changes are not warranted based on the wide therapeutic index and the efficacy observed with vardenafil in Phase III studies that were not restricted with respect to food.