Pharmacokinetic data were evaluated in 10 term neonates with seizures after intravenous administration of lorazepam, 0.05 mg/kg or 0.1 mg/kg. All seizure activity ceased, with no adverse effects. Pharmacokinetic data revealed a decreased volume of distribution and clearance, and a prolonged half-life in comparison with data from older children and adults. These findings are consistent with physiologic differences in the neonate.