Background and Objective: Child- and adolescent-onset psychopathology is known to increase the risk for developing substance use and substance use disorders (SUDs). While pharmacotherapy is effective in treating pediatric psychiatric disorders, the impact of medication on the ultimate risk to develop SUDs in these youth remains unclear. Methods: We conducted a Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) systematic review of peer-reviewed literature published on PubMed through November 2021, examining pharmacological treatments of psychiatric disorders in adolescents and young adults and their effect on substance use, misuse, and use disorder development. Results: Our search terms yielded 21 studies examining the impact of pharmacotherapy and later SUD in attention-deficit/hyperactivity disorder (ADHD), two studies on Major Depressive Disorder, and three studies on psychotic disorders. The majority of these studies reported reductions in SUD (N = 14 sides) followed by no effects (N = 10) and enhanced rates of SUD (N = 2). Studies in ADHD also reported that earlier-onset and longer-duration treatment was associated with the largest risk reduction for later SUD. Conclusions: Overall, pharmacological treatments for psychiatric disorders appear to mitigate the development of SUD, especially when treatment is initiated early and for longer durations. More studies on the development of SUD linked to the effects of psychotherapy alone and in combination with medication, medication initiation and duration, adequacy of treatment, non-ADHD disorders, and psychiatric comorbidity are necessary.
Keywords: adolescent; pharmacotherapy; psychiatric disorders; substance use.