Recent advances in adjunctive therapy for epilepsy: focus on sodium channel blockers as third-generation antiepileptic drugs.

Voltage-gated sodium channel blockers like phenytoin and carbamazepine have long been used in the treatment of epilepsy. Brain sodium channels continue to be an important target of many newer second-generation (fosphenytoin, oxcarbazepine, lamotrigine, felbamate, topiramate, zonisamide) and third-generation (eslicarbazepine, brivaracetam, carisbamate, fluorofelbamate, elpetrigine, lacosamide, rufinamide, safinamide, vinpocetine) antiepileptic drugs (AEDs). Some of the newer drugs show either state-dependent antiepileptic action or sodium channel subtype selectivity, although most agents do not differentiate between these channel subtypes. The present review highlights the preclinical and clinical efficacy, pharmacokinetics, drug interactions and adverse event profiles. It also addresses AED selection of sodium channel blockers that constitutes the third generation of AEDs.