Clobazam for refractory childhood seizure disorders--a valuable supplementary drug.

Clobazam is a new benzodiazepine recently introduced in Canada on an experimental basis. We report our experience with 27 children (average age 9.1 years) with severe intractable seizure disorders. All had mixed seizures (41% focal plus generalized, 59% mixed generalized) and 93% were mentally retarded. Eighty-five percent had multiple daily seizures and all had been on an average of 6 other anticonvulsants in the past. Forty-one percent of our patients responded to clobazam with a reduction of greater than 75% in seizure frequency and 15% had no further seizures. Tolerance to clobazam which could not be overcome by dose increases developed in 26% of patients. Forty-four percent of non-responders had exacerbations of their seizures shortly after starting clobazam, however 43% of these patients had reductions in comedications simultaneously. Side effects of clobazam in responders were minimal. We conclude that clobazam shows sufficient promise to warrant further trials in more benign seizure disorders in children.