An introduction to antiepileptic drugs.

In recent years, the number of commercially available antiepileptic drugs (AEDs) has increased steadily. Although this may complicate management choices, it also offers welcome new options to individualize treatment more effectively. Because each of the available AEDs differs from others in many clinically relevant properties, opportunities to tailor drug treatment to the characteristics of the individual patient have never been greater. Properties that are especially important in drug selection in patients with epilepsy include spectrum of efficacy in different seizure types, adverse effects profile, pharmacokinetic properties, susceptibility to cause or be a target of clinically important drug-drug interactions, ease of use, and cost. Other factors that need to be considered in tailoring drug choice include availability of user-friendly pediatric formulations, and potentially favorable effects on co-morbid conditions. In fact, a number of AEDs are efficacious and widely prescribed in additional indications, particularly psychiatric disorders, migraine prophylaxis, and neuropathic pain. Recently, advances have been made in understanding the mechanisms of actions of AEDs at the molecular level. While a fully mechanistic approach to the clinical use of these agents is not yet feasible, knowledge of mechanisms of action offers useful clues in predicting their efficacy profile and spectrum of potential adverse effects.