Abstract
The relation between the serum levels and the oral dose of phenobarbital and carbamazepine was studied in children with chronic anticonvulsant treatment, and also the therapeutic levels of phenobarbital to prevent recurrence of the febrile and afebrile general convulisions were studied.The ratio of the serum level (μg/ml) to the dose (mg/kg) of phenobarbital was 3.1-3.4 in children under 3 years of age, 3.88 in children of 4-5 years of age and 5.48 in children over 6 years of age.There was no relationship between the serum levels and the oral dose of carbamazepine.Serum levels of carbamzepine in a day showed a marked fluctuation which was assumed due to rapid plasma half life of this drug, and seemed to explain the lack of relationship between the levels and doses.
Of 35 children with febrile convulsion whose serum lvels of phenobarbital were examine shortly before or after febrile episodes, only one of 14 children whose serum levels of phenobarbital were 16μg/ml or more had convulsion.On the other hand, 5 of 21 children whose serum levels of phenobarbital were 15 u g/ml or less had convulsions.Therapeutic levels of phenobarbital to prevent recurrence of febrile convulsion were suggested to be more than 16μg/ml. We could not find a clear-cut therapeutic range of phnobarbital to control afebrile generalized convulsion.
