Interactions between trileptal(oxcarbazepine) and Adriamycin rdf (DOXOrubicin)
DOXOrubicin and oxcarbazepine (Moderate Drug-Drug)
MONITOR: Based on in vitro data, coadministration with oxcarbazepine may decrease the plasma concentrations of drugs that are substrates of the CYP450 3A4 and 3A5 isoenzymes. The mechanism is accelerated clearance due to induction of CYP450 3A activities by oxcarbazepine. In one study, a single dose of oxcarbazepine (600 mg) had no effect on the pharmacokinetics of felodipine, a CYP450 3A4 substrate, while repeated doses (450 mg twice a day) decreased the peak plasma concentration and area under the concentration-time curve of felodipine (10 mg once daily) by 34% and 28%, respectively. Likewise, in a single case study, cyclosporine trough concentrations decreased to subtherapeutic levels a little over 2 weeks after addition of oxcarbazepine in a renal transplant patient. These results indicate that enzymatic induction occurs after multiple doses.
MANAGEMENT: Caution is advised if oxcarbazepine must be used concurrently with medications that undergo metabolism by CYP450 3A4 and/or 3A5, particularly those with a narrow therapeutic range. Dosage adjustments as well as clinical and laboratory monitoring may be appropriate for some drugs whenever oxcarbazepine is added to or withdrawn from therapy.
