Pharmacokinetics of intravenous chlorpheniramine in children.

The disposition of chlorpheniramine was examined in seven children, 6-14 years of age, following a 0.1 mg/kg iv dose. Postinjection serum chlorpheniramine levels in each subject declined biexponentially, with the greatest intersubject variability occurring in the initial distribution of the drug. The volume of distribution at steady state ranged from 1.20 to 5.46 liters/kg. The chlorpheniramine serum clearance varied approximately twofold (234-470 ml/hr/kg) and generally decreased with age. The chlorpheniramine elimination half-life in children (mean of 9.6 hr) appeared shorter than that in adults, probably due to higher chlorpheniramine serum clearance in children.