Levetiracetam in the treatment of Lennox-Gastaut syndrome.

Lennox-Gastaut syndrome is an epileptic encephalopathy characterized by multiple seizure types, mental retardation, and a slow spike-and-wave pattern on electroencephalography. Medical intractability is common. We identified a case series of six patients diagnosed with Lennox-Gastaut syndrome in which levetiracetam was initiated as add-on therapy for the management of seizures. At follow-up, four patients experienced 100% reduction of their myoclonic seizures; two patients had greater than 50% reduction of their atonic seizures, and four patients experienced 100% reduction in their generalized tonic-clonic seizures. Tonic seizures were not responsive to treatment. The most common side effect was irritability; the most positive change involved alertness. In this small sample, levetiracetam appeared effective in reducing seizures in Lennox-Gastaut syndrome. This preliminary study is limited by its retrospective design and small number of patients, but positive findings warrant a larger scale, multicenter study.