Hyperactivity in preschoolers and the effect of methylphenidate.

Observations of nursery behavior and tests of cognitive style and motor impulsivity were carried out with 28 hyperactive preschool children of normal intelligence and 26 matched control children. The hyperactive group was also observed and tested on methylphenidate and placebo. Methylphenidate was found to reduce hyperactivity at home, but it did not improve nursery behavior or psychological functioning. Unwanted side effects made the drug less useful at this age than in older hyperactive children.