Current issues in the treatment of epilepsy.

General principles of antiepileptic drug (AED) therapy are reviewed, current issues involving the use and monitoring of AEDs are examined, promising investigational agents are briefly reviewed, and situations that require potentially difficult decisions about long-term care are discussed. The initial treatment should be monotherapy with a first-line AED for the particular seizure disorder. The usual approach is to maximize seizure control and minimize the adverse effects of AED therapy. Current issues involving the pharmacokinetics, use, and monitoring of the conventional AEDs phenytoin, phenobarbital, primidone, carbamazepine, valproic acid, ethosuximide, benzodiazepines, and acetazolamide are discussed. AED therapy may have adverse effects on behavior and cognition. The risk of teratogenicity with well-monitored AED therapy is probably low, and severe hepatotoxicity is uncommon. Because carbamazepine, phenobarbital, phenytoin, and primidone all have enzyme induction properties, a number of clinically important interactions are possible. Issues related to discontinuing AED therapy, serum concentration monitoring, and generic interchange of AED products are addressed. Whether AEDs should be used to prevent recurrent febrile seizures, alcohol withdrawal seizures, or seizures in patients with head trauma or stroke must be considered. The treatment of seizure disorders is a complex process involving identification of the seizure disorder, selection and monitoring of an appropriate AED(s), and consideration of adverse effects and drug interactions. Whether therapy should be discontinued after a prolonged seizure-free period, compliance issues, and whether to treat certain conditions prophylactically also must be considered.