Pharmacogenetic-Guided Antidepressant Prescribing (PGx-GAP) in Adolescents

Summary

Depression is common and has serious effects on adolescents and their families. While ~ 150,000 Canadian adolescents take antidepressant medications each year, many do not feel better with medication. Some adolescents can react badly to the medication - a side effect or adverse reaction - and some adolescents do not have an improvement in their depression.

Prescribing medication is often a ‘trial-and-error’ process, where adolescents take a medication for a month or more to see if it will work. If it does not work, they might repeat this process with another medication.

Our team aims to address the trial-and-error approach to prescribing medications. We want to evaluate a new way to match adolescents to an antidepressant medication that is more likely to be safe and beneficial for them. We will enrol adolescents into a study that uses a small amount of their saliva to conduct a single genetic test.

The results from this test show whether:
1) their genes might make it harder for their body to process some antidepressant medications (causing unexpected side effects or adverse reactions), or
2) their genes may cause their body to process an antidepressant medication too fast, which means they may not benefit from that medication or may need a higher dose to benefit. We want doctors to use these genetic test results when they make a decision about which medication to prescribe.

Because we do not know if this approach will work for adolescents yet, we need to compare it with usual prescribing practices. A random half of the participants in this study will receive a report based on their genetic test and a random half will receive a report based on usual prescribing guidelines. All participants will receive a full pharmacogenetic report at the end of the study.