Clinical Pharmacology of Phenobarbital in Neonates: Effects, Metabolism and Pharmacokinetics

Title:Clinical Pharmacology of Phenobarbital in Neonates: Effects, Metabolism and Pharmacokinetics

Volume: 12 Issue: 1

Author(s): Gian M. Pacifici

Affiliation:

Keywords: Dosing, metabolism, neonate, pharmacokinetics, phenobarbital, serum-levels.

Abstract: Phenobarbital is an effective and safe anticonvulsant drug introduced in clinical use in 1904. Its mechanism of action is the synaptic inhibition through an action on GABA_A. The loading dose of phenobarbital is 20 mg/kg intravenously and the maintenance dose is 3 to 4 mg/kg by mouth. The serum concentration of phenobarbital is up to 40 g/ml. Nonresponders should receive additional doses of 5 to 10 mg/kg until seizures stop. Infants with refractory seizures may have a serum concentration of phenobarbital of 100 g/ml. Phenobarbital is metabolized in the liver by CYP2C9 with minor metabolism by CYP2C19 and CYP2E1. A quarter of the dose of phenobarbital is excreted unchanged in the urine. In adults, the half-life of phenobarbital is 100 hours and in term and preterm infants is 103 and 141 hours, respectively. The half-life of phenobarbital decreases 4.6 hours per day and it is 67 hours in infants 4 week old.

Cite this article as:

Pacifici M. Gian, Clinical Pharmacology of Phenobarbital in Neonates: Effects, Metabolism and Pharmacokinetics, Current Pediatric Reviews 2016; 12 (1) . https://dx.doi.org/10.2174/1573397111666151026223914