We meta-analyzed 15 longitudinal studies, consisting of 2565 individuals, to test whether treatment with medication (typically methylphenidate) for ADHD predicted later substance outcomes. Across 5 types of substance (ie, alcohol, cocaine, marijuana, nicotine, and nonspecific drugs) for lifetime use and abuse or dependence, results indicated that substance outcomes were comparable to those individuals who did and did not receive medication. That is, children with ADHD who were treated with stimulant medication were generally equivalent to children with ADHD without stimulant medication histories on all substance outcomes. Moreover, this effect was evident for nicotine and cocaine abuse or dependence, a particularly important consideration given that these outcomes were particularly sensitive to early ADHD in a recent meta-analysis.38
