felbamate and Anisindione Interactions

Interactions between felbamate and Anisindione (anisindione)

anisindione and felbamate (Moderate Drug-Drug)

MONITOR: Felbamate has been reported to increase the anticoagulant effect of warfarin. The mechanism may be inhibition of warfarin metabolism via the CYP450 system in the liver. According to a single case report, the addition of felbamate necessitated a reduction of approximately 50% in warfarin dosage to maintain the target INR. However, causal effect has not been definitively established. Other oral anticoagulants could interact with felbamate in a similar manner.

MANAGEMENT: Close monitoring of the prothrombin time or the INR is recommended if felbamate and an oral anticoagulant must be used together. The anticoagulant dose may need to be decreased or temporarily stopped. Patients should be advised to notify their physician if they experience any signs of excessive anticoagulation, such as unusual or prolonged bleeding, bruising, vomiting, change in stool or urine color, headache, dizziness, or weakness.