Treatment of febrile seizures with intermittent clobazam

Fifty children, 24 female and 26 male, with ages varying from 6 to 72 months (mean = 23.7 m.) that experienced at least one febrile seizure (FS) entered a prospective study of intermittent therapy with clobazam. Cases with severe neurological abnormalities, progressive neurological disease, afebrile seizures, symptomatic seizures of other nature, or seizures during a central nervous system infection were excluded. Seizures were of the simple type in 25 patients, complex in 20 and unclassified in 5. The mean follow-up period was 7.9 months (range = 1 to 23 m.), and the age at the first seizure varied from 5 to 42 months (mean = 16.8 m.). Clobazam was administered orally during the febrile episode according to the child's weight: up to 5 kg, 5 mg/day; from 5 to 10 kg, 10 mg/day; from 11 to 15 kg, 15 mg/day, and over 15 kg, 20 mg/day. There were 219 febrile episodes, with temperature above 37.8 degrees C, in 40 children during the study period. Twelve children never received clobazam and 28 received the drug at least once. Drug efficacy was measured by comparing FS recurrence in the febrile episodes that were treated with clobazam with those in which only antipyretic measures were taken. Ten children (20%) experienced a FS during the study period. Of the 171 febrile episodes treated with clobazam there were only 3 recurrences (1.7%), while of the 48 episodes treated only with antipyretic measures there were 11 recurrences (22.9%), a difference highly significant (p < 0.0001). Adverse effects occurred in 10/28 patients (35.7%), consisting mainly in vomiting, somnolence and hyperactivity. Only one patient had recurrent vomiting which lead to drug interruption. These effects did not necessarily occurred in every instance the drug was administered, being present in one febrile episode and not in the others. We conclude that clonazepam is safe and efficacious in preventing FS recurrence. It may be an alternative to diazepam in the intermittent treatment of FS recurrence.