In:
Antimicrobial Agents and Chemotherapy, American Society for Microbiology, Vol. 48, No. 10 ( 2004-10), p. 3794-3800
Abstract:
The population pharmacokinetics of pyrimethamine (PYR) and sulfadoxine (SDX) for a group of 32 children with congenital toxoplasmosis was investigated by nonparametric modeling analysis. A one-compartment model was used as the structural model, and individual pharmacokinetic parameters were estimated by Bayesian modeling. PYR (1.25 mg/kg of body weight) and SDX (25 mg/kg) were administered orally every 10 days for 1 year, with adjustment of the dose to body weight every 3 months. Drug concentrations were measured by high-performance liquid chromatography. A total of 101 measurements in serum were available for both drugs. Mean absorption rate constants, volumes of distribution, elimination rate constants, and half-lives were 0.915 h −1 , 4.379 liters/kg, 0.00839 h −1 , and 5.5 days for PYR and 1.659 h −1 , 0.392 liters/kg, 0.00526 h −1 , and 6.6 days for SDX, respectively. Wide interindividual variability was observed. The estimated minimum and maximum concentrations of PYR in serum differed 8- and 25-fold among patients, respectively, and those of SDX differed 4- and 5-fold, respectively. Increases in the concentration of PYR were observed for eight children, and increases in the SDX concentration were observed for seven children. Serum PYR-SDX concentrations are unpredictable even when the dose is standardized for body weight. The concentrations of the PYR-SDX combination that are most efficacious for children have not yet been established. A model such as ours, associated with long-term follow-up, is needed to study the correlation between exposure to these two drugs and clinical outcome in children.
Type of Medium:
Online Resource
ISSN:
0066-4804
,
1098-6596
DOI:
10.1128/AAC.48.10.3794-3800.2004
Language:
English
Publisher:
American Society for Microbiology
Publication Date:
2004
detail.hit.zdb_id:
1496156-8
SSG:
12
SSG:
15,3
Bookmarklink
