PHARMACOKINETICS OF THE ORALLY-ADMINISTERED DECONGESTANTS PSEUDOEPHEDRINE AND PHENYLPROPANOLAMINE IN CHILDREN

Background: There is little published, objective information about pse udoephedrine and phenylpropanolamine in the treatment of children. Our goal was to determine the pharmacokinetics of these medications in yo ung subjects. Methods: In two sequential double-blind, parallel-group, single-dose studies, 21 children received either pseudoephedrine, 30 or 60 mg, or placebo, and 20 children received either phenylpropanolam ine, 20 or 37.5 mg, or placebo. Before dosing and at intervals up to 7 hours after dosing, serum pseudoephedrine or phenylpropanolamine conc entrations were measured, and pulse and blood pressure were recorded. In two children receiving each drug, these tests were also performed a t 12 and 24 hours, and urine was collected from 0 to 12 and from 12 to 24 hours. Results: In children, the mean (+/-SEM) terminal eliminatio n half-life values for pseudoephedrine, 3.1 +/- 0.5 hours, and for phe nylpropanolamine, 2.6 +/- 0.6 hours, were significantly shorter than t hose found by other investigators in adults. Pharmacokinetics were not dose dependent in the dose ranges studied.Conclusion: Further studies of pseudoephedrine and phenylpropanolamine should be performed in chi ldren with the use of objective measurements. The widespread use of th ese medications in young subjects should be reevaluated.