Investigation of phenobarbital-carbamazepine-valproic acid interactions using population pharmacokinetic analysis for optimisation of antiepileptic drug therapy: an overview.

Antiepileptic drugs are associated with a wide range of drug interactions. Although monotherapy with antiepileptic drugs is preferred, patients with multiple seizure types or refractory disease generally require various combinations of antiepileptic drugs. Pharmacokinetic interactions between antiepileptic drugs represent a major complication of epilepsy treatment with polytherapy. It is important to be aware of possible interactions, so as to anticipate clinical effects and to reduce the risk of both toxicity and seizures worsening when a drug is added to, or withdrawn from, the patient's antiepileptic drug regimen. This report is an overview of the drug-drug interactions between antiepileptic drugs (phenobarbital<-->carbamazepine, carbamazepine<-->valproic acid and phenobarbital<-->valproic acid) by population pharmacokinetic analysis.