Annual prescriptions for attention-deficit/hyperactivity disorder (ADHD) medications in Ontario rose by 157 percent between 2015 and 2023, according to a new study from researchers at ICES, North York General Hospital, and The Hospital for Sick Children (SickKids).
The study analyzed data from more than 15 million people aged 5 to 105 living in Ontario. Researchers found that about 4 percent of this population—591,224 individuals—had received one or more stimulant prescriptions during the study period.
ADHD is a neurodevelopmental disorder affecting roughly 1.6 to 5 percent of people worldwide. Stimulant medications such as amphetamines are commonly prescribed to manage symptoms and can improve health and social outcomes for those diagnosed with ADHD.
Dr. Daniel Myran, family physician, ICES scientist, and Research Chair in Family and Community Medicine at North York General, commented on the findings: "The upward trend in prescriptions around the world highlights an important challenge. On one hand, it is likely showing progress towards identifying and treating ADHD in groups who have historically been underdiagnosed. However, the size of the increases also raises concerns about mis- or over-diagnosis, which can result in exposure to adverse side effects of medications and a missed opportunity to treat other mental health conditions."
Researchers pointed out several possible reasons for the increase in stimulant prescriptions. These include a true rise in individuals with ADHD symptoms due to changing social or environmental factors like increased screen time; better identification of previously undiagnosed cases; or misdiagnosis and overdiagnosis.
The study noted that there was an acceleration in prescription rates beginning in 2020. Dr. Myran explained: "The acceleration in 2020 coincides with the COVID-19 pandemic during which there was a large increase in online content about adult ADHD diagnoses and the emergence of private virtual clinics offering rapid ADHD assessments. These changes may both increase awareness and reduce barriers to diagnosis for people who have ADHD, but also increase the risk of overdiagnosis."
One limitation highlighted by researchers was that they did not have data indicating whether these medications were being prescribed appropriately.
Dr. Yaron Finkelstein, Staff Physician and Senior Scientist at SickKids as well as Canada Research Chair in Pediatric Drug Safety and Efficacy, emphasized the importance of ongoing monitoring: "With around seven per cent of children and a nearly three-fold increase in adults being prescribed stimulants for ADHD than before the pandemic, ongoing research and clear clinical guidance are essential to ensuring these medications are used safely and appropriately."
