Ontario Sees 157% Increase in People Starting ADHD Medications

ADHD drugs are shown in a file photo. Jenny Kane/AP Photo

The number of people receiving prescriptions for attention deficit/hyperactivity disorder (ADHD) in Ontario has risen more than 157 percent in less than a decade, with a marked increase among adults.

A study published in JAMA Network Open this week analyzed all prescriptions for stimulant drugs like Ritalin and Adderall that were dispensed in the province from 2015 to 2023. Researchers found there was a 157 percent rise in the overall annual new stimulant prescriptions by 2023 compared to 2015.

Researchers at the Institute for Clinical Evaluative Sciences (ICES), North York General, and The Hospital for Sick Children said the number of prescriptions for ADHD treatment grew throughout the study period with a notable acceleration in 2020, when COVID-19 lockdowns began. Prescriptions increased by 28 percent annually that year, compared to just 7 percent from 2015 to 2019.

“The rapid increase in stimulant use, particularly in adults, underscores the need for enhanced clinical training and evidence-based guidance in adult ADHD diagnosis,” the report said. It noted that findings in United States testing were similar, but that the Ontario study “reveals a broader and more accelerated increase in stimulant prescribing.”

Growing Use Among Adults and Children

Prescriptions for ADHD medication were up in all age groups and across both genders, but the most notable change throughout the study period was seen in adult females between 18 and 44.

The largest change was observed in the 25 to 44 age group, with increases of roughly 421 percent for women and 220 percent for men. There was also a marked difference among 18-to-24 year-olds. ADHD med usage increased 369 percent among females and 128 percent among males.

There were also increases among older adults. ADHD prescriptions in the 45 to 64 age range shot up 188 percent for women and 119 percent for men. The smallest increase was among those aged 65 years or older with females seeing an 18 percent increase and males a 2 percent increase.

A similar study released earlier this fall outlined comparable findings in British Columbia. The study, published in The Lancet, found the pre-pandemic average of newly diagnosed adult ADHD was 8.8 cases per 100,000 population monthly. That rose to 19.2 during the pandemic. Rates continued to rise after the pandemic ended, the B.C. researchers found. The monthly rate jumped by 107 percent in July 2021 and subsequently increased by 1.5 percent each month, resulting in an average of 34.8 cases per 100,000 in the post-pandemic period.

The study also identified the most rapid increase in females diagnosed with ADHD, estimating a growth rate that was more than twice that of males during the pandemic.

There was also a considerable increase in the number of children beginning to use ADHD prescriptions, according to the Ontario study, but the spike among adults was much larger.

As with the adults, females accounted for more of the newly prescribed medications.

There was a 191 percent increase observed among girls aged 10 to 14, in contrast to a 67.5 percent rise for boys within the same age range, and a 49 percent increase in girls aged five to nine compared to a 32 percent increase for boys in that group.

Historically, the diagnostic criteria for ADHD focused on hyperactivity, which is more common among males. More attention has recently been paid to women’s under-diagnosed inattentive symptoms, such as struggling to stay focused and establish priorities.

The CADDAC, Canada’s national charity for people with ADHD, says many young girls go undiagnosed because they often present as quiet and undemanding in a classroom setting, spending time daydreaming rather than causing a ruckus.

“For this reason, girls are frequently not diagnosed until later in adolescence or adulthood,” the CADDAC says. “The primarily inattentive presentation of ADHD more frequently found in females, although not exclusively, can often go undiagnosed resulting in later coexisting disorders of anxiety and depression.”

Diagnosis Concerns

The increasing level of stimulant prescribing in high-income countries has raised concerns about potential over-diagnosis, misuse, and adverse effects, the researchers said.

They said there is insufficient data regarding the appropriate prescription of the medication and noted some individuals may have been misdiagnosed if a condition that causes similar symptoms is incorrectly deemed ADHD. Being over-diagnosed, when milder symptoms are incorrectly diagnosed as ADHD, is also a possibility, they said.

The sharp rise in ADHD prescriptions could be attributed to a rise in screen time, the study said. However, it was also noted that heightened public awareness and acceptance of ADHD symptoms, along with the identification of individuals who were previously undiagnosed, could be contributing factors in the increase.

ADHD is one of the most common neurodevelopmental disorders in Canada, affecting approximately 1.8 million Canadians, or one out of every 21 people in the country, according to the CADDAC, Canada’s national charity for people with ADHD.

It is a chronic neurodevelopmental disorder that can cause hyperactivity and a lack of focus among other symptoms.