Evaluating the safety and efficacy of felbamate in the context of a black box warning: A single center experience.

ABSTRACT

INTRODUCTION: Felbamate was approved in 1993 to treat partial seizures with and without secondary generalization in adults and in Lennox-Gastaut Syndrome in children. Its use was later restricted when rare but fatal cases of aplastic anemia and hepatic failure were identified. METHODS: This single center analysis retrospectively evaluated the safety and efficacy of felbamate in a cohort of children, adolescents, and adults with epilepsy. RESULTS: A chart review identified 103 patients taking felbamate. The range of felbamate dose was 300-4500 mg (mean 1800 ± 900 mg). The duration of therapy ranged from 1 month to 20 years (mean duration 35 ± 45 months). Eighteen (17.5%) subjects experienced adverse events including insomnia, nausea, vomiting, decreased appetite, weight loss, gastric discomfort, diarrhea, mood and behavioral problems, high blood pressure, headache, and elevated liver enzymes. Out of these, 6 (5.9%) patients discontinued the therapy. No hepatic failure or agranulocytosis was observed. Fifty-nine (57.72%) patients achieved ≥ 50% reduction in seizure frequency, and 30 (29.12%) patients achieved seizure freedom. CONCLUSIONS: These findings suggest that felbamate is safe, well tolerated, and effective in treatment of various types of epilepsy syndromes.