title: Population pharmacokinetic investigation of digoxin in Japanese infants and young children.
abstract: To establish the role of patient characteristics in estimating doses of digoxin for infants and young children using routine therapeutic drug monitoring data, the steady-state blood-level data (n = 245) after repetitive oral administration in 117 hospitalized infants and young children were analyzed using nonlinear mixed effects modeling (NONMEM), a computer program designed for analyzing drug pharmacokinetics in study populations through pooling of data. Analysis of the pharmacokinetics of digoxin was accomplished using a 1-compartment pharmacokinetic model. Estimates generated by NONMEM indicated that the clearance of digoxin (CL/F; L/h) was influenced by the following demographic variables: total body weight (TBW), presence of congestive heart failure (CHF), and infant-young children clearance factor (trough serum concentration of digoxin; Conc). These influences could be modeled by the equation CL/F (L/h) = 0.302 · TBW (kg)¹·¹⁷ · 0.905(CHF) · Conc (trough serum digoxin concentration >1.7 ng/mL)⁻⁰·⁵⁴⁰; F = 0.754, where CHF is 1 for presence of congestive heart failure, 0 otherwise; F is bioavailability, 1 for elixirs, 0.754 for powders; and Conc⁻⁰·⁵⁴⁰ is 1 for digoxin concentration <1.7 ng/mL. Clinical application of the model to patient care may permit selection of an appropriate initial maintenance dose, thus enabling the clinician to achieve the desired therapeutic effect. However, the digoxin dosage regimen for the individual patient should be based on a careful appraisal of his or her clinical need for the drug.
authors.affiliation: Laboratory of Evidence-Based Pharmacotherapy, Daiichi University of Pharmacy, 22-1 Tamagawa-Cho, Minami-Ku, Fukuoka 815-8511, Japan. yukawa@daiichi-cps.ac.jp
authors.forename: Miho
authors.initials: M
authors.lastname: Yukawa
authors.forename: Eiji
authors.initials: E
authors.lastname: Yukawa
authors.forename: Fumihiro
authors.initials: F
authors.lastname: Suematsu
authors.forename: Takako
authors.initials: T
authors.lastname: Takiguchi
authors.forename: Hirohito
authors.initials: H
authors.lastname: Ikeda
authors.forename: Hatsumi
authors.initials: H
authors.lastname: Aki
authors.forename: Masao
authors.initials: M
authors.lastname: Mimemoto
mesh_terms: D044466:Asian People / Q000706:statistics & numerical data*; D002316:Cardiotonic Agents / Q000493:pharmacokinetics*; D002675:Child, Preschool; D004077:Digoxin / Q000493:pharmacokinetics*; D016903:Drug Monitoring / Q000706:statistics & numerical data; D005260:Female; D006333:Heart Failure / Q000097:blood; D006801:Humans; D007223:Infant; D008297:Male; D015233:Models, Statistical; D017711:Nonlinear Dynamics; D019999:Pharmaceutical Solutions / Q000493:pharmacokinetics*; D011208:Powders / Q000493:pharmacokinetics*; D015203:Reproducibility of Results; D012189:Retrospective Studies
chemical_list: D002316:Cardiotonic Agents; D019999:Pharmaceutical Solutions; D011208:Powders; D004077:Digoxin