nafcillin and Cartia xt Interactions

Interactions between nafcillin and Cartia xt (diltiazem)

nafcillin and diltiazem (Moderate Drug-Drug)

MONITOR: Concurrent administration of nafcillin has been reported to result in a large reduction in the plasma concentration of nifedipine. A similar reaction and possible loss of efficacy may be expected if nafcillin were used concurrently with other calcium channel blockers including diltiazem, felodipine, nicardipine, or verapamil. Nafcillin is a potent inducer of CYP450 3A4 enzymes which metabolize these calcium channel blockers.

MANAGEMENT: If these calcium channel blockers must be or are being used with nafcillin, the patient should be monitored closely for change in the efficacy of the calcium channel blocker, when nafcillin is added to or removed from the patient's drug therapy. Use of a different antibiotic may be appropriate.