Methylphenidate and ADHD: influence of age, IQ and neurodevelopmental status.

Sixty-nine children with attention deficit hyperactivity disorder (ADHD) underwent blind methylphenidate trials. 36 had ADHD alone (with or without a learning disability) and 33 had additional neurodevelopmental disorders. Of the children with ADHD alone, 88 per cent improved significantly on methylphenidate. This did not differ significantly from the 69 per cent response rate for children with ADHD and other neurodevelopmental disorders. The results confirm and add to the research literature indicating that ADHD children who are of preschool age and/or who have co-existing neurological disorders may benefit from methylphenidate.