Skønt der ikke er foretaget specifikke interaktionsundersøgelser, kan samtidig anvendelse af andre potente CYP3A4- inhibitorer (som itraconazol) forventes at medføre vardenafil plasmaniveauer sammenlignelige med dem frembragt af ketoconazol.
Although specific interaction studies have not been conducted, the concomitant use of other potent CYP3A4 inhibitors (such as itraconazole) can be expected to produce vardenafil plasma levels comparable to those produced by ketoconazole.