The effect of methylphenidate on urinary catecholamine excretion in hyperactivity: a partial replication.

Children with attention deficit disorder with hyperactivity were treated with methylphenidate HCl (0.74 +/- 0.2 mg/kg/day) for 2 weeks in an open trial to assess changes in the urinary excretion of catecholamines and behavior. The purpose of this study was to confirm earlier work that methylphenidate has a distinctly different effect on urinary 3-methoxy-4-hydroxyphenylglycol (MHPG) excretion as compared to earlier studies with dextroamphetamine. Results confirmed the earlier finding that methylphenidate does not significantly change urinary MHPG excretion. No significant relationship was found between behavioral change and any of the urinary catecholamines or metabolites measured.