These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


PUBMED FOR HANDHELDS

Search MEDLINE/PubMed


  • Title: Altered phenytoin pharmacokinetics in children with severe, acute traumatic brain injury.
    Author: Stowe CD, Lee KR, Storgion SA, Phelps SJ.
    Journal: J Clin Pharmacol; 2000 Dec; 40(12 Pt 2):1452-61. PubMed ID: 11185666.
    Abstract:
    The purpose of this study was to determine if phenytoin protein binding and metabolism were altered in prepubescent pediatric patients within the first 10 days following severe, acute traumatic brain injury. Patients (n = 10) received phenytoin loading doses (15-20 mg/kg) followed by a maintenance regimen (7 mg/kg/day) initiated within 12 hours of the loading dose. Phenytoin serum concentrations were measured serially on days 1, 2, 3, 5, 7, 9, and 10 at 1, 6, and 12 hours. Time-invariant and time-variant Michaelis-Menten pharmacokinetic models were fit to the unbound phenytoin concentration-time data (ADAPT II). Albumin concentrations significantly decreased over time (p < 0.001) and were predictive of the phenytoin binding ratio (r2 = 0.373, p < 0.0001). The time-variant model provided a superior fit of the data in 7 patients with no difference between models in 3 patients. Rapid inhibition of metabolism (Vmaxbaseline = 2.82 +/- 2.35 mg/kg/day) was observed initially following injury. This was followed by induction of metabolism as reflected by a Vmaxinduced of 20.79 +/- 13.71 mg/kg/day, which was approximately twofold higher than reported values for nonstressed children. Children with severe, acute neurotrauma were found to have markedly altered protein binding and phenytoin metabolism.
    [Abstract] [Full Text] [Related] [New Search]