Diltiazem Dofetilide

Clinically important, potentially hazardous interactions with cyclosporine, diltiazem, dofetilide, erythromycin, grapefruit, ketoconazole, quinidine, ritonavir, simvastatin, sotalol, thioridazine, verapamil, ziprasidone... 

IV Ibutilide Dofetilide Verapamil Diltiazem BepridiP Inhibit the slow inward calcium current, minimal effect (decrease) on ventricular action potential, major effects on the atrioventricular node to slow conduction velocity and increase the ERP. 

Inhibitors of the CYP3A4 isoenzyme could increase systemic dofetilide exposure. Inhibitors of this isoenzyme (e.g., macrolide antibiotics, azole antifungal agents, protease inhibitors, serotonin reuptake inhibitors, amiodarone, cannabinoids, diltiazem, grapefruit juice, nefazadone, norfloxacin, quinine, and zafirlukast) should be cautiously coadministered with TIKOSYN, because they can potentially increase dofetilide levels... 

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