Children taking medication to treat attention deficit hyperactivity disorder (ADHD) are not at a greater risk of abusing drugs or alcohol later on in adulthood, researchers report.
The study, published in the Journal of the American Medical Association (JAMA) Psychiatry, were based on meta-analysis of 15 previous studies, dating from 1980 to 2012, that included 2,600 children, and young adults with ADHD. The participants were between the ages of 3 and 28 and some were prescribed medication and some of them, were not.
"Previously, there was evidence for both increased risk and decreased risk for substance problems related to stimulant medication in the treatment of ADHD," said study author Kathryn Humphreys, a doctoral student in psychology at University of California, Los Angeles.
"The present study suggests that, on average, children who received stimulant medication treatment for ADHD are at no differential risk for these substance outcomes than their counterparts who did not receive medication treatment," she said.
The researchers analyzed data related to substance use or abuse of each drug separately. For every category they looked at - alcohol, nicotine, marijuana, cocaine and other drugs - Ritalin and similar stimulants weren't tied to a clear increase or decrease in future use or abuse.
"The scientific evidence suggests that the risk for alcohol and substance problems later in development, in adolescence or adulthood, doesn't seem to be strongly tied to whether or not children were previously... treated with stimulant medication," said Steve Lee, a UCLA associate professor of psychology, according to a press release.
"These results provide an important update and suggest that treatment of attention-deficit/hyperactivity disorder with stimulant medication neither protects nor increases the risk of later substance use disorders," the UCLA researchers said.
The findings oppose a widely cited decade-old study that claimed ADHD medications reduce a person's risk of developing drug dependency. That study, which UCLA researchers called "highly influential as evidenced by its high citation rate," incorporated data from only six studies.
"The present meta-analysis included substantially more studies, including several unpublished studies," the researchers noted.
The participants in the study, led by researchers from the University of California, Los Angeles (UCLA) were from California, New York, Michigan, Pennsylvania, Massachusetts, Germany and Canada. ADHD is believed to occur in five to 10 per cent of US children. A recent analysis of US government data by the New York Times found that as many as one in five teenage boys is diagnosed with the disorder.