OBJECT DRUGS
PRECIPITANT DRUGS
Calcium Channel Blockers:
- Diltiazem (Cardizem, etc.)
- Verapamil (Isoptin, etc.)
Comment:
Ivabradine is a CYP3A4 substrate, and CYP3A4 inhibitors such as diltiazem or verapamil may increase the risk of toxicity. In addition to increasing ivabradine plasma concentrations, the negative inotropic effect of diltiazem and verapamil may add to that of ivabradine, increasing the risk of bradycardia.
Class 2: Use Only if Benefit Felt to Outweigh Risk
- Use Alternative: Calcium channel blockers other than diltiazem and verapamil are unlikely to inhibit the metabolism of ivabradine, and are also less likely to increase the risk of ivabradine-induced bradycardia. The product information for ivabradine states that concurrent use of diltiazem and verapamil should be avoided.
- Monitor: If the combination is used, monitor for ivabradine toxicity, including bradycardia.