Purpose: We report a double-blind, placebo-controlled crossover study of lamotrigine (LTG) as add-on treatment in therapy-resistant, generalized epilepsy in children and adolescents (n = 30).
Methods: Twenty patients had Lennox-Gastaut syndrome. Each patient acted as his or her own control. LTG and placebo were randomly added to existing antiepileptic medication (AEDs). The LTG dosage was individualized in an open phase preceding the placebo/treatment phase. Patients who responded to LTG in the open phase went on to the double-blind phase. "Responders " were defined as patients with a >50% seizure reduction or less severe seizures or both, or improved behavior or improved motor skills or both. "Nonresponders" were defined as children who showed no positive effects of LTG with plasma levels of < or = 10 microg/ml or children who had adverse events during the open phase.
Results: There was a clear statistically significant reduction of seizure frequency in LTG compared with placebo treatment. None of the children studied showed abnormal biochemical or hematologic findings, or changes in plasma levels of concomitantly administered AEDs.
Conclusions: LTG is a well-tolerated and effective treatment in children with intractable generalized epilepsies, including those with Lennox-Gastaut syndrome. The study design allowed a double-blind placebo-controlled assessment of LTG although the participating children used 19 different AED combinations at entry.