Cognitive impairment and dementia in prisoners of war

The pharmacologic basis of antiepileptic drug action

The development of medications used in the treatment of epilepsy has accelerated over the past decade, and has benefited from a parallel growth in our knowledge of the basic mechanisms underlying neuronal excitability and synchronization. This understanding of the pharmacologic basis of antiepileptic drug (AED) action has, in large part, arisen from recent advances in cellular and molecular biology, coupled with avenues of drug discovery that have departed somewhat from the largely empiric approaches of the past. Physicians now have available to them an ever-growing armentarium of AEDs, necessitating a firmer appreciation of their mechanisms of action if more rational approaches toward both clinical application and research are to be adopted. An important example in this regard is the concept of rational polypharmacy for patients with epilepsy who are refractory to monotherapy. This review summarizes our current understanding of the molecular targets of clinically significant AEDs, comparing and contrasting their differing mechanisms of action.

Topiramate

Six studies are cited to demonstrate that topiramate is effective as adjunctive therapy for refractory partial-onset seizures in adults. Subsequent studies indicate that topiramate is also effective as monotherapy in adults and as adjunctive therapy for partial-onset seizures in children, tonic-clonic seizures of nonfocal origin in children and adults, and drop attacks in Lennox-Gastaut syndrome. Adverse effects for adults and children included dizziness, fatigue, ataxia, confusion, somnolence, nephrolithiasis, paresthesia, and weight loss. More adverse effects were observed at higher doses. Topiramate exhibits rapid absorption, long duration of action, and minimal interaction with other antiepileptic drugs.

Use of new antiepileptic drugs in the treatment of childhood epilepsy

The management of epilepsy in children requires careful evaluation, classification, and pharmacologic treatment. With classic antiepileptic drugs (AEDs), at least 25% of children remain refractory to appropriate therapy. The past decade has allowed the introduction of a number of newer AEDs for treatment of both adults and children with epilepsy. These include felbamate, gabapentin, lamotrigine, topiramate, tiagabine, and vigabatrin. Emerging information regarding the efficacy of these AEDs in treating childhood epilepsy syndromes suggests advantages for many patients. Limited data are available that define the optimal use of new AEDs in pediatric patients. Further research must be completed to validate the positive effects described in existing clinical trials of the new AEDs in the treatment of childhood epilepsy.