Treatment of neonatal seizures with carbamazepine.

Carbamazepine has been used in adults and children for over 30 years. In spite of an excellent therapeutic and side-effect profile in older children, it has never been used as a primary anticonvulsant in neonates. This is the first report of the long-term use of carbamazepine in neonates. Ten full-term neonates with two or more seizures due to hypoxic-ischemic encephalopathy were given 10 mg/kg of carbamazepine as a loading dose via nasogastric tube. Twenty-four hours later, the first five patients began a maintenance regimen of 21 mg/kg/daily, and the remaining five patients began a maintenance regimen of 15 mg/kg/daily, all via nasogastric tube. Therapy was continued for 3 to 9 months. Drug levels were monitored every 2 to 4 hours during the first 24 hours, and on days 2, 4, 8, 15, 30, 45, and 60, and monthly thereafter. Absorption of carbamazepine was excellent even in sick neonates. Therapeutic levels were reached in 2 to 4 hours in all patients. Peak levels were achieved in 4 to 16 hours (mean, 9.2 +/- 4.2). Elimination half-life was 24.5 hours. Levels dropped precipitously around 8 to 15 days and thereafter declined slowly over the next 3 months. Seizure control was excellent; only two patients had one seizure each during the first 10 hours. There were no gastrointestinal, hepatic, hematologic, renal, or dermatologic side effects. This preliminary study shows that carbamazepine may be an effective anticonvulsant for neonatal seizures.