Drug Interaction Report

Consumer information for this interaction is not currently available.

MONITOR: Coadministration with inducers of CYP450 3A4 may decrease the plasma concentrations of ivabradine and its active N-desmethylated metabolite, both of which are primarily metabolized by the isoenzyme. In 12 healthy volunteers, administration of a single 10 mg dose of ivabradine following pretreatment with the potent CYP450 3A4 inducer St. John's wort (300 mg three times daily for 14 days) decreased mean ivabradine peak plasma concentration (Cmax) and systemic exposure (AUC) by approximately 53% and 62%, respectively, compared to administration of ivabradine alone. Mean Cmax and AUC of the N-desmethylated metabolite, which is equipotent to ivabradine and circulates at concentrations approximately 40% that of ivabradine, decreased by 25% and 32%, respectively. The extent to which other, less potent inducers of CYP450 3A4 may interact with ivabradine is unknown.

MANAGEMENT: Caution is advised during concomitant use of ivabradine with CYP450 3A4 inducers. The potential for decreased efficacy of ivabradine should be considered.

Do not consume grapefruit or grapefruit juice during treatment with ivabradine. Grapefruit juice can significantly increase the blood levels and effects of ivabradine, which may result in excessive slowing of heart rate or other conduction disturbances. Talk to your doctor if you have any questions or concerns. Let your doctor know if you experience significant decreases in heart rate or symptoms such as dizziness, fatigue, or low blood pressure. Also seek medical attention if you develop heart palpitations, chest pressure, or worsened shortness of breath, as these may be symptoms of atrial fibrillation caused by ivabradine. It is important to tell your doctor about all other medications you use, including vitamins and herbs. Do not stop using any medications without first talking to your doctor.