A major Swedish study has found that medication for attention-deficit/hyperactivity disorder (ADHD) may provide benefits beyond managing core symptoms — including significantly reducing the risk of suicide, substance misuse, traffic accidents, and criminal activity.
The research, published in the BMJ, analysed data from nearly 149,000 people aged 6 to 64 who were diagnosed with ADHD in Sweden between 2007 and 2020. The team compared individuals who began ADHD medication within three months of diagnosis to those who did not, tracking them for an average of two years.
ADHD affects around 5% of children and 2.5% of adults globally, with symptoms typically emerging before age 12. The disorder can cause inattention, impulsivity, hyperactivity, forgetfulness, and restlessness, often impacting school, work, and relationships.
While patients are familiar with common side effects of medication — such as insomnia, appetite loss, and irritability — the new findings suggest there may also be important long-term protective effects. According to the study, medication use was linked to a 17% reduction in suicide-related behaviours, a 15% drop in alcohol or drug misuse, a 12% decrease in transportation accidents, and a 13% decline in criminality.
Dr. Samuele Cortese, a co-author and professor at the University of Southampton, called the results “extremely important from a public health and clinical perspective,” noting that they bring researchers closer to establishing a causal link between ADHD treatment and these reduced risks.
Previous studies have suggested untreated ADHD can lead to anxiety, addiction, job instability, and legal trouble. However, without large-scale randomised controlled trials — the gold standard in medical research — it has been difficult to prove that medication itself drives these improvements. This study aimed to mimic such trials by closely matching treated and untreated patients.
Researchers believe the benefits may be tied to the drugs’ ability to reduce impulsivity — which could lower aggressive or criminal behaviour — and to improve focus, reducing distractions that can lead to accidents.
The study does have limitations. Prescription data does not guarantee patients took their medication, and the analysis excluded incidents too minor to appear in medical or legal records. Still, Cortese said the results should be part of the conversation between doctors and patients.
“When doctors discuss ADHD drugs, they often focus on side effects — which are important — but rarely on the risks of not treating the condition,” he said. “If left untreated, there can be unfortunate consequences, and now we have evidence that medication may help reduce those risks.”
