Abstract: | The effect of acute treatment with the new antiepileptic drug (AED) levetiracetam (Keppra) on the frequency of interictal epileptiform discharges (IEDs) was evaluated in a double-blind, placebo-controlled, crossover study with therapeutic drug monitoring and serial electroencephalographic (EEG) observations. Acute (500 mg twice daily) and chronic (individualized, 500-1000 mg twice daily) doses of levetiracetam were administered as an add-on to current AED treatment. Efficacy was tested by measuring the frequency of IEDs in EEG recordings and the number of seizures. A single acute dose of levetiracetam induced a reduction of IEDs in eight out of ten patients. During the acute phase, an insufficient number of seizures occurred for analysis. During chronic treatment over 8 weeks, seven patients showed a reduction in seizure frequency (responder rate), and one patient remained seizure free. No correlation was seen between levetiracetam levels and IED frequency. Doses of levetiracetam of up to 2000 mg/day were well tolerated, and no interactions were seen with concomitant AEDs. |