The authors report on a one-year follow-up of 76 hyperactive boys who had participated in a comparative study of methylphenidate, imipramine, and placebo. They found that there was a higher rate of discontinuance of imipramine than of methylphenidate in this sample and that both medications decreased the boys' rate of weight gain but had no significant effect on growth in height. This findings is of concern because larger doses than were used in this study are in use elsewhere. Teachers reported that the group of boys who had discontinued either medications showed continued hyperactivity and behavior problems in the classroom at one year. The two treatment groups showed continued improvement at one year in classroom and home behavior and did not suffer significantly from each other.