In the treatment of the patient with epilepsy not only seizure control but quality of life issues are important aspects of management. Aspects that have an impact on the quality of life include seizure frequency and severity, social functioning, psychological well-being, disease specific measures, and general health status.

Lamotrigine (LTG) inhibits repetitive high frequency firing in depolarised neurones by selectively prolonging slow inactivation of the sodium channel, thereby suppressing the release of excitatory amino acids. It has been shown to be effective in 11 pivotal double-blind add-on trials in patients with refractory partial seizures with or without secondary generalisation. Subsequent anecdotal data support its efficacy for typical and atypical absences, myoclonic jerks, tonic or clonic seizures, Lennox- Gastaut syndrome and infantile spasms. Most recently LTG has been compared with carbamazepine and phenytoin in double-blind trials in patients with newly diagnosed partial and primary and secondary generalised tonic-clonic seizures. At the doses used, its efficacy was similar to the older agents for all seizure types, but LTG was better tolerated than both of the older agents. The commonest sideeffects with LTG include headache, nausea, diplopia, dizziness, ataxia and tremor. Rash occurs in fewer than 5% patients. Its incidence can be reduced by starting treatment with a low dose, particularly in patients receiving concomitant sodium valproate which inhibits LTG metabolism. Enzyme inducers, such as carbamazepine, phenytoin and phenobarbital, accelerate its elimination, but LTG itself has no effect on hepatic metabolic processes. A pharmacodynamic interaction with carbamazepine necessitates a dosage reduction in some patients when LTG is introduced. LTG is a new antiepileptic agent with a long elimination half-life, a broad spectrum of activity, and a wide therapeutic ratio.

Gabapentin is a novel antiepileptic drug that has recently been introduced in Canada. Although its mechanism of action remains to be defined gabapentin is effective in a number of seizure models which predict its efficacy in partial and tonic-clonic seizures. Clinical studies support the clinical efficacy of gabapentin as adjunctive therapy in adults with epilepsy with partial and secondarily generalized tonic-clonic seizures. Gabapentin has a favorable pharmacokinetic profile and is generally well tolerated. More clinical data are required on the role of gabapentin in children and additional monotherapy experience is required before the role of gabapentin in the overall treatment of epilepsy can be better defined.

Vigabatrin (VGB) is a recently-released antiepileptic drug which works by a clearlydefined mechanism of action: inhibition of GABA transaminase leading to an elevation of brain GABA concentration. It has been proven effective, mainly as an add-on agent, in complex partial and secondarily generalized seizures in both adults and children as well as in infantile spasms in both short and long-term controlled studies. World-wide experience now includes over 150,000 patients exposed to the drug. VGB has a favorable pharmacokinetic profile since it has little protein-binding, is mainly excreted unchanged by the kidney and has a long effective half-life allowing once or twice daily dosing. It is generally well-tolerated with very few cognitive effects but may cause significant behavioral side effects such as agitation, irritability, depression or psychosis in approximately 2-4% of cases. Mild weight gain and possible exacerbation of absence and myoclonic seizures are other reported adverse effects. The role of VGB in other childhood epileptic syndromes apart from West syndrome is still being defined.

In the last few years a number of new antiepileptic drugs ahve been introduced for the treatment of epilepsy. In addition to the standard antiepileptic drugs, clobazam, vigabatrin, gabapentin, and lamotrigine have been introduced. The choice of the best antiepileptic drug for an individual patient has become more complex. In this review the clinical benefits of the standard and the new antiepileptic drugs are presented.