Effects of methylphenidate treatment in children with mental retardation and ADHD: Individual variation in medication response

Deborah A. Pearson, David M. Lane, Cynthia W. Santos, Charles D. Casat, Susan W. Jerger, Katherine A. Loveland, Laura P. Faria, Rosleen Mansour, Jill A. Henderson, Christa D. Payne, John D. Roache, David Lachar, Lynne A. Cleveland

Research output: Contribution to journalArticle

29 Scopus citations


Objective: Individual variation in cognitive and behavioral response to methylphenidate (MPH) was investigated in children with mental retardation and attention-deficit/hyperactivity disorder. Method: Twenty-four children (mean age 10.9 years, SD = 2.4) participated in a placebo-controlled, double-blind, crossover trial with 0.15-, 0.30-, and 0.60-mg/kg b.i.d. doses of MPH. Parent and teacher behavioral ratings, as well as cognitive task performance, were assessed at each dose. Results: Relative to placebo, most children with attention-deficit/hyperactivity disorder and mental retardation showed some degree of behavioral and cognitive improvement with MPH treatment. However, fewer of these children made substantial gains (>30% improvement, relative to placebo) with MPH treatment. At the highest dose, 55% of the children showed substantial behavioral gains and 46% made substantial gains in cognitive task performance. However, there was substantial independence between changes in behavior and changes in cognitive performance. Conclusions: At the 0.60-mg/kg MPH dose, more children showed substantial cognitive and behavioral gains than those who showed substantial declines in a ratio of more than 5:1. However, it may be prudent to assess cognitive change as well as behavioral effects because improvements in the former do not necessarily forecast improvements in the latter in children with attention-deficit/hyperactivity disorder and mental retardation.

Original languageEnglish (US)
Pages (from-to)686-698
Number of pages13
JournalJournal of the American Academy of Child and Adolescent Psychiatry
Issue number6
Publication statusPublished - Jun 2004



  • Attention-deficit/hyperactivity disorder
  • Behavior
  • Children
  • Cognition
  • Mental retardation
  • Methylphenidate

ASJC Scopus subject areas

  • Developmental and Educational Psychology
  • Psychiatry and Mental health

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