Drug Interaction Report

Consumer information for this interaction is not currently available.

ADJUST DOSE: Coadministration with inhibitors of CYP450 3A4 and/or 2C9 may increase the plasma concentrations of vardenafil, which is primarily metabolized by the former and secondarily by the latter. The possibility of prolonged and/or increased pharmacologic effects of vardenafil should be considered.

MANAGEMENT: Dosage adjustments may be appropriate for vardenafil whenever a CYP450 3A4 and/or 2C9 inhibitor is added to or withdrawn from therapy based on efficacy and patient tolerance. The manufacturer recommends that an initial vardenafil dosage of 2.5 to 5 mg be used in patients treated concomitantly with a potent CYP450 3A4 inhibitor such as erythromycin, itraconazole, ketoconazole, indinavir, and ritonavir. No specific dosage recommendations are available for coadministration with less potent inhibitors. Patients should be advised to promptly notify their doctor if they experience pain or tightness in the chest or jaw, irregular heartbeat, nausea, shortness of breath, visual disturbances, syncope, or prolonged erection (greater than 4 hours).

Grapefruit juice may increase the blood levels of certain medications such as vardenafil. You may want to limit your consumption of grapefruit and grapefruit juice during treatment with vardenafil. However, if you have been regularly consuming grapefruit or grapefruit juice with the medication, then it is advisable for you to talk with your doctor before changing the amounts of these products in your diet, as this may alter the effects of your medication. Contact your doctor if your condition changes or you experience increased side effects. Orange juice is not expected to interact.