ADHD Research Today is a free monthly online journal that collates and summarizes the latest research about ADHD, including details on attention-deficit hyperactivity disorder, drugs, treatment, symptoms. | ||||||||
|
Pharmacokinetics of methylphenidate in preschoolers with attention-deficit/hyperactivity disorder.Wigal SB, Gupta S, Greenhill L, Posner K, Lerner M, Steinhoff K, Wigal T, Kapelinski A, Martinez J, Modi NB, Stehli A, Swanson J Child Development Center,University of California, Irvine, California 92612, USA. sbwigal@uci.edu OBJECTIVE: The aim of this study was to compare the pharmacokinetics of immediate-release methylphenidate (MPH) in preschool and school-aged children with attention-deficit/hyperactivity disorder (ADHD). METHODS: Preschool children 4-5 years (n = 14) and school-aged children 6-8 years (n = 9) with diagnoses of ADHD were titrated to an effective dose of MPH based on parent, teacher, and clinician ratings in a protocol specified by the Preschoolers with ADHD Treatment Study (PATS) and then attended a laboratory school where the single morning dose of immediate release MPH was administered. Blood samples for measurement of MPH concentrations were obtained predose, and at 1, 2, 4, and 6 hours postdose. A nonlinear model was used to derive three pharmacokinetic (PK) values for analysis: Peak plasma concentration (C(max)), half-life (t(1/2)), and clearance (CL). RESULTS: The two groups did not differ in the mean mg dose of MPH (p = 0.33), or in the weight-adjusted mg/kg dose (p = 0.20). Dose-normalized C(max) was significantly higher (p = 0.003), and clearance was significantly slower (p = 0.0002) in preschool than in school-aged children. CONCLUSIONS: In this sample, age significantly affected absorption and metabolism of MPH, so that preschool children had greater exposure than school-aged children to the same weight-adjusted dose. These data suggest additional studies should be performed to characterize age-related differences in PK properties of MPH that may inform practitioners about dosing strategies based on the age and size of children being treated. Published 10 May 2007 in J Child Adolesc Psychopharmacol, 17(2): 153-64.
© 2004-2008 ADHD Research Today. All Rights Reserved. |
| ||||||
