ADHD medication linked to lower risk of suicide attempts, substance abuse, and criminality

People who take medication for ADHD have a lower risk of suicide attempts, substance abuse, traffic accidents, and criminality than people with ADHD who do not take medication. This is shown in a new study by researchers from Karolinska Institutet and University of Southampton, published in the journal BMJ.
ADHD, which affects about 5 percent of children and 2.5 percent of adults globally, is associated with an increased risk of suicide attempts, substance abuse, accidents, and crime, among other things.
The researchers behind the study wanted to investigate whether ADHD medication reduces the risk of these outcomes by analyzing Swedish national registry data between 2007 and 2020.
A total of nearly 150,000 individuals between the ages of 6 and 64 with newly diagnosed ADHD were included. The average age in the group was 17, and 41 percent were women. Of these, 57 percent started medication, with methylphenidate being the most common drug.
The researchers compared people who had started medication within three months of diagnosis with those who had not, and assessed the outcomes over two years after diagnosis.
Reduction in the risk of serious outcomes
The results showed that ADHD medication was associated with a significant reduction in the risk of several serious outcomes: suicide attempts decreased by 17 percent, substance abuse by 15 percent, traffic accidents by 12 percent, and criminality by 13 percent. The effects were even more pronounced in certain subgroups—for example, a 25 percent reduction in substance abuse and criminality was noted in individuals who had had recurring problems with these issues.

One possible explanation is that the medication leads to reduced impulsivity, which can reduce the risk of crime by curbing aggressive behavior, as well as improved attention, which can reduce the risk of traffic accidents by reducing distractions,” says the study's last author, Zheng Chang, a researcher at the Department of Medical Epidemiology and Biostatistics, Karolinska Institutet. He continues:
“These results provide evidence that ADHD medication can affect important health and societal outcomes, which should be taken into account both in clinical practice and in the public debate on drug treatment.”
The study is a collaboration between Karolinska Institutet and the University of Southampton. The study was funded by the Swedish Research Council and the Swedish Research Council for Health, Working Life and Welfare, Forte, among others. Some researchers have received fees from pharmaceutical companies, but for work outside the current study.
Publication
”ADHD drug treatment and risk of suicidal behaviours, substance misuse, accidental injuries, transport accidents, and criminality: emulation of target trials”, Le Zhang, Nanbo Zhu, Arvid Sjölander, Mikail Nourredine, Lin Li, Miguel Garcia-Argibay, Ralf Kuja-Halkola, Isabell Brikell, Paul Lichtenstein, Brian M D’Onofrio, Henrik Larsson, Samuele Cortese, Zheng Chang, BMJ, online August 13, 2025, doi: 10.1136/ bmj-2024‑083658