Rational conversion from antiepileptic polytherapy to monotherapy.

For patients with epilepsy, the goal of treatment is to achieve seizure freedom with minimal or no adverse events. Around 60%-70% of newly diagnosed patients will achieve this goal with single antiepileptic drug (AED) therapy, and there is universal agreement that prescription of a single agent constitutes best practice for such patients. For the 30%-40% of patients with poorly controlled epilepsy, treatment options are less clear and many receive add-on therapy with one or more AEDs in an attempt to improve seizure control. Because the therapeutic gain from adjunctive therapy is often marginal and may be complicated by increased drug toxicity, converting individual patients from polytherapy to monotherapy is a common clinical problem facing physicians managing patients with epilepsy today. Evidence from studies with both standard and new AEDs shows that selected patients, including those with previously resistant epilepsy, can be converted successfully from polytherapy to monotherapy without loss of seizure control and in some cases with improved seizure control. Adverse effects can be minimised during the conversion process by slow withdrawal of the first prescribed drug, while increasing the daily dose of the add-on AED to achieve optimal therapeutic doses/levels for continued monotherapy. Deciding which drug(s) to withdraw and which to continue as monotherapy requires adequate consideration of individual patient needs with reference to clinical profiles (seizure type and severity), previous response to individual AEDs and the pharmacokinetic and pharmacodynamic implications of withdrawal.