Update on Antiseizure Medications 2025

This article is an update from the article on antiseizure medication therapy published in the three previous Continuum issues on epilepsy and is intended to cover the vast majority of agents currently available to neurologists in the management of patients with epilepsy. This article addresses antiseizure medications individually, focusing on key pharmacokinetic characteristics, indications, and modes of use.

Since the most recent version of this article was published, one new antiseizure medication, ganaxolone, has been approved by the US Food and Drug Administration (FDA), and the indications of some approved medications were expanded. Older antiseizure medications are effective but have tolerability and pharmacokinetic disadvantages. Several newer antiseizure medications have undergone comparative trials demonstrating efficacy equal to and tolerability at least equal to or better than older antiseizure medications as first-line therapy for focal epilepsy. These agents include lamotrigine, oxcarbazepine, levetiracetam, topiramate, zonisamide, and lacosamide. Pregabalin was found to be less effective than lamotrigine. Lacosamide, pregabalin, and eslicarbazepine have undergone successful trials of conversion to monotherapy for focal epilepsy. Other newer antiseizure medications with a variety of mechanisms of action are suitable for adjunctive therapy.

Knowledge of antiseizure medication pharmacokinetics, efficacy, and tolerability profiles facilitates the choice of appropriate antiseizure medication therapy for patients with epilepsy. Rational antiseizure medication combinations should avoid antiseizure medications with unfavorable pharmacokinetic interactions or pharmacodynamic interactions related to mechanism of action.