Co-medication and potential drug interactions among patients with epilepsy

Management of epilepsy usually involves the long-term use of antiepileptic drugs (AEDs) and a substantial percentage of patients require polytherapy to control their seizures [1]. The use of multiple AEDs poses a risk of drug interactions including enzyme induction or inhibition, alterations in protein-binding and expression of transporter proteins [2]. It may result in decreased efficacy or increased toxicity of AEDs. The use of some older AEDs (e.g. carbamazepine or phenytoin), known as potent hepatic enzyme-inducers is a major source of pharmacokinetic interactions between AEDs and other medications commonly used in elderly population, such as statins, antidepressants or neuroleptics [2,3,4].