Felbamat ve Primidon etkileşimi

IT IS NOT KNOWN WHETHER CONCOMITANT USE OF OTHER ANTIEPILEPTIC DRUGS AND/OR OTHER DRUGS AFFECT THE INCIDENCE OF HEPATIC FAILURE.

Use in Conjunction with Other Antiepileptic Drugs (see DOSAGE AND ADMINISTRATION ) The addition of Felbatol ® to antiepileptic drugs (AEDs) affects the steady-state plasma concentrations of AEDs.

CBZ epoxide ↓ ↑ ↓ Phenobarbital ↑ ↓ Specific Effects of Felbatol® on Other Antiepileptic Drugs Phenytoin Felbatol ® causes an increase in steady-state phenytoin plasma concentrations.

Effects of Other Antiepileptic Drugs on Felbatol ® Phenytoin Phenytoin causes an approximate doubling of the clearance of Felbatol ® (felbamate) at steady-state and, therefore, the addition of phenytoin causes an approximate 45% decrease in the steady-state trough concentrations of Felbatol ® as compared to the same dose of Felbatol ® given as monotherapy.

The net effect of these interactions is summarized in Table 2: Table 2 Steady-State Plasma Concentrations of Felbatol When Coadministered With Other AEDs AED Coadministered AED Concentration Felbatol ® Concentration Phenytoin ↑ ↓ Valproate ↑ ↔ No significant effect.

Neonatal hemorrhage, with a coagulation defect resembling vitamin K deficiency, has been described in newborns whose mothers were taking primidone and other anticonvulsants.