Drug selection for the newly diagnosed patient: when is a new generation antiepileptic drug indicated?

Treatment options in epilepsy have increased dramatically since the early 1990s with the introduction of nine new generation antiepileptic drugs (AEDs) (felbamate, gabapentin, lamotrigine, levetiracetam, oxcarbazepine, tiagabine, topiramate, vigabatrin and zonisamide). This makes drug selection much more complicated and challenging. This review discusses drug selection in patients with newly diagnosed epilepsy and in particular the role of new AEDs in this population. The choice of treatment should always be based on a careful comparison of the risk-benefit ratio for the different treatment options and the outcome of such evaluation may be different in patients with new onset compared with chronic epilepsy. Efficacy, tolerability and safety are the main criteria for selection of AEDs and any first line drug for patients with newly diagnosed epilepsy must have demonstrated satisfactory efficacy as monotherapy in that patient population. So far, of the new AEDs only lamotrigine, oxcarbazepine and topiramate have documentation sufficient to be granted licence for use as monotherapy in most European countries. Because the new generation AEDs have failed to demonstrate improved effectiveness as monotherapy, old generation AEDs such as carbamazepine and valproate remain drugs of first choice for partial and generalised seizures, respectively. However, there are special situations and populations where a new AED may be a reasonable first line drug. These include vigabatrin in West syndrome associated with tuberous sclerosis, lamotrigine as alternative to valproate in idiopathic generalised seizures in women of childbearing potential and lamotrigine for the treatment of epilepsy in the elderly population. The role of the new generation AEDs is likely to become more prominent as more experience is gained.