ADHD and substance misuse

There has been great interest in the overlap between ADHD and substance use disorder (SUD). ADHD is a common neurobehavioural disorder of childhood that places the individual at elevated risk for later SUD. Studies have shown that 25–40% of adults and adolescents with SUD have ADHD. Although the exact link between the two disorders is still unclear, it appears their connection is complex, and involves the interplay between various biological, behavioural, and genetic factors. Early pharmacotherapy of ADHD does not increase SUD, and, in fact, appears to reduce cigarette smoking and SUD. In individuals with ADHD and SUD, stabilization of SUD is recommended initially, with consideration of adjunct non-stimulant and extended release stimulant medications. More research on the mechanisms of overlap between the disorders, preventative effects of early ADHD treatment on SUD, and concurrent treatments for ADHD and SUD are necessary.