The Cannabidiol for At Risk Youth (CanARY) study is testing a potential new treatment called cannabidiol (CBD) for helping people with symptoms that might indicate risk of a psychotic disorder. CBD is a non-psychoactive treatment, meaning it does not give you a ‘high’.
About this study
Participants will take varying doses of CBD or a placebo every day for 12 weeks and meet with researchers once a month to check for any symptoms. Symptoms vary for individuals but can include:
- Feeling low in mood
- Feeling paranoid
- Seeing or hearing things that they know aren’t there
Some people might worry their thoughts are being heard, may not feel right in themselves, or have more difficulty than usual coping with work, school or relationships.
Anticipated enrolment close date: October 2025
Contact the Research team for more information.
Who can take part
Eligible participants will:
- Be aged 12 to 25 years (inclusive)
- Have sufficient fluency in English to complete assessments
- Be able to give informed consent (parental/guardian consent will be obtained for participants aged under 18 years)
- Meet ultra-high risk (UHR) criteria
What's involved
- Participants will take either 600mg of CBD, 1000mg of CBD or a placebo (no CBD) every day for 12 weeks.
- Researchers will meet with participants once a month throughout the 12 weeks to ask about their symptoms and how they have been going (either online or in person).
- Blood and urine samples will be taken at three points during the study. An optional hair sample may be taken once or twice during the study.

Ethics
All research in Australia involving human participants is reviewed by an independent group called a Human Research Ethics Committee (HREC). The ethical aspects of this research study have been approved by the Royal Melbourne Hospital HREC.
This study is being carried out according to the National Statement on Ethical Conduct in Human Research (2007). This statement protects the interests of people who agree to participate in human research studies.