DONATIONS AT WORK HIGHLIGHTS 2025/26

Pharmacogenomics of Stimulant Treatment Response

Meet Emily

Since middle school, Emily has struggled with symptoms of Attention-Deficit/Hyperactivity Disorder (ADHD). The challenges became especially apparent when the COVID-19 pandemic struck. At the time, Emily was in Grade 7 and found it particularly tough to stay focused while learning online.

In high school, the symptoms became even more debilitating. Paying attention and even staying awake in classes that weren’t particularly interesting or stimulating was really difficult. Emily first pursued a diagnosis in Grade 10, however, didn’t receive one at that time. Meanwhile, things continued to deteriorate.

In my first semester of Grade 12, I ended up getting 54 percent in social studies – I did fine on the tests, but didn’t hand in any of the assignments. My teachers just thought I was lazy because there was no proof that I was actually dealing with something. — Emily

The drug dilemma

For most children and adolescents with ADHD, psychostimulants such as Concerta are the first-line pharmacological treatment. However, the effects — both positive and negative — of various drugs and dosages can affect young people very differently. Though medication is highly-effective in controlling or tempering ADHD symptoms for some, others have little to no positive change and some even experience adverse side effects with no benefit.

Historically, a young person might need to try a number of different medications and dosages for up to a few months each in order to rule out the ones that don’t work and find the right one. This process can be physically and mentally taxing for a child and their family, especially if they experience side effects like sleep disruption, changes in appetite or headaches.

With some other pharmacological treatments, like antidepressants, there are genetic markers that help guide dosing and drug choice for certain patients. However, there is limited evidence to support prescribing when it comes to ADHD medications and no established guidelines for physicians to follow.

Personalizing prescriptions

Thanks to generous community support, researchers in Calgary are gathering the data needed to pinpoint patterns that show how genetics contribute to the efficacy of ADHD drugs in individuals.

Through a study called Pharmacogenomics of Stimulant Treatment Response (PGx-STaR), scientists are looking to fill the current gap in knowledge and identify genomic markers that would guide prescribing for young people with ADHD.

PGx-STaR participants each receive a personalized report outlining how their DNA influences their body’s reactions to and metabolism of certain drugs. Collectively, the data is shaping the bigger picture, demonstrating that certain genetic makeups are more or less likely to see benefits or experience unwanted side effects from medications. Eventually, this information could contribute to a prescribing guide so physicians know which of the drug options is most likely to work for a specific patient, reducing the need to trial multiple options and potentially endure unnecessary negative side effects.

This study is a win-win. Our research team is gathering invaluable data to inform timely and effective care for generations of young people with ADHD to come. Meanwhile, our participants get to learn a bit about their genetic makeup, which may be a useful tool in guiding their own medication journeys in the future. — Sam Siu, project coordinator

Building the future