NCT06290063 · University of Colorado, Boulder
Cannabidiol and Older Adult Cannabis Users
(QUARTz)
What this study is about
Cannabis use increased 10 fold among adults over the age of 65 between 2014 and 2016 but very little data exists on the extent of their harmful effects on health and behavior.
View original scientific description
Cannabis use increased 10 fold among adults over the age of 65 between 2014 and 2016 but very little data exists on the extent of their harmful effects on health and behavior. The overarching goal of this project is to test a novel harm reduction strategy in which older individuals who seek to use cannabis for pain, anxiety or mood problems (depression/anxiety) will be randomly assigned to one of three conditions in an 8 week randomized controlled trial: hemp-derived CBD+THC, hemp-derived CBD-THC, or placebo. This work has the ability to directly inform individual choices regarding the use of cannabis products among older adults, and direct policy decisions regulating cannabis formulations on the legal market.
Who can participate
This study lists these criteria on ClinicalTrials.gov. A study coordinator reviews eligibility during screening — this page does not determine whether you qualify.
Inclusion criteria
- At least 60 years of age
- Able to provide informed consent
- Must have used a cannabis product at least once with no negative effects
- Must not have been regularly using any cannabis products (\<3x/month) in the last 6 months
- Female participants must be postmenopausal
- Liver function tests (Alanine transaminase (ALT) and
- Aspartate transaminase (AST)) must show levels no greater than 2x the upper normal limits for age
- Must be currently taking medication/s for pain, sleep, and/or mood
Exclusion criteria
- Blood alcohol level \> 0 at screening (to sign consent form)
- Report of other drug use (cocaine, opiates, methamphetamine) in the past 90 days or fail urine screen for any of these drugs
- Past or current diagnosis, or family history of diagnosis of psychosis
- Current use of anti-epileptic medications (e.g. clobazam, sodium valproate)
- Current use of medications known to have major interactions with Epidiolex (buprenorphine, leflunomide, levomethadyl acetate, lomitapide, mipomersen, pexidartinib, propoxyphene, sodium oxybate, and/or teriflunomide).
- Current use of antipsychotic medications
- Currently undergoing chemotherapy (to prevent drug interactions)
Where
- Boulder, Colorado
Frequently asked questions
What is a clinical trial?
A clinical trial is a research study that tests new medical treatments, drugs, devices, or procedures to determine their safety and effectiveness. Trials are carefully designed and monitored to protect participants while advancing medical knowledge.
Is it safe to participate?
Clinical trials follow strict safety guidelines and ethical standards. Trials must be reviewed and approved, and participants are closely monitored by medical professionals throughout the study. You can withdraw at any time if you choose.
Will I be compensated?
Many clinical trials offer compensation for your time, travel expenses, and inconvenience. The specific compensation varies by study and will be discussed during the screening process. All study-related medical care is typically provided at no cost to participants.
Will I receive a placebo instead of treatment?
When effective treatment exists, participants typically receive either the standard treatment plus the study intervention, or the standard treatment plus placebo. You would not be denied effective care. Placebos are primarily used when no proven treatment is available, or in addition to standard care. Your trial consent form will clearly explain what treatments you may receive.
Can I leave a trial if I change my mind?
Absolutely. Participation in clinical trials is completely voluntary. You have the right to withdraw from the study at any time, for any reason, without penalty or loss of benefits to which you are otherwise entitled.
How long does a clinical trial last?
Trial duration varies widely depending on the study design and purpose. Some trials last just a few weeks, while others may continue for months or years. The study coordinator will provide specific timeline information during your screening call.
Data: ClinicalTrials.gov · synced Jun 10, 2026 · Source of record for eligibility and locations