Behavioral, situational, and temporal effects of treatment of ADHD with methylphenidate

Objective: To determine the behavioral, situational, and temporal effects of 4 months of methylphenidate (MPH) treatment for attention-deficit hyperactivity disorder (ADHD). Method: Ninety-one children with ADHD were randomly assigned to receive either MPH (titrated to a target dose of 0.7 mg/kg twice a day) or a placebo. Treatment effects were investigated with measures sensitive to various behaviors (core and associated symptoms), situations (home and school), time periods (morning and afternoon, after reaching the target dose, and after 4 months of treatment), and side effects. Results: MPH treatment improved symptoms of ADHD and oppositional behavior at school, both in the morning and afternoon, but not at home. Side effects (increase in physiological and affective symptoms, lack of weight gain) were significantly more frequent with MPH than with placebo treatment. Benefit was evident after titration, but the onset of some side effects was delayed. Side effects were reported by parents but not by teachers. Conclusions: Positive effects of MPH on behavior are evident in the classroom, but with MPH given twice daily, parents do not report that MPH improves behavior at home. Greater impact on home behavior may require three times daily MPH and combined treatments.