NCT06982950 · Oregon Health and Science University
Cannabis Association With Sleep Study
(CaSS)
What this study is about
The purpose of this study is to learn more about cannabis use, sleep, and stress, and whether there is any relationship between the three.
View original scientific description
The purpose of this study is to learn more about cannabis use, sleep, and stress, and whether there is any relationship between the three.
Interventions
OTHER
Manipulation of Sleep Duration
After a baseline assessment of sleep, participants will undergo either 2 nights of restricted sleep (4 hour time in bed) followed by a recovery sleep, OR 3 nights of an extended sleep opportunity (10 hour time in bed)
Primary outcome measures
Daily Cannabis Use Frequency
Time frame: Assessed in surveys performed 4 times per day, and across the entire 21-day study
The number of smoking/vaping sessions per day.
Wake After Sleep Onset (WASO)
Time frame: 21 days
Wake after sleep onset (measured in minutes) will be assessed each night from actigraphy; larger value indicates greater disruptions to sleep.
Cortisol Awakening Response
Time frame: 8 nights
Salivary cortisol levels assessed as the difference between waking and peak levels assessed \~30-45 minutes after awakening.
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
- fluent in English
- 5\<BMI\<40 kg/m2
- no shift work in the last 12 months
- no travel across time zones in the last 2 months.
Exclusion criteria
- Chronic disease-Medical history/prior diagnosis of the following:
- cardiometabolic disease (e.g., myocardial infarction, angina, diabetes)
- essential hypertension
- hepatic impairment
- severe obstructive sleep apnea
- restless legs syndrome
- neurological disease (e.g., early onset dementia)
- unstable psychiatric disorders (e.g., bipolar disorder, schizophrenia, major depression with suicidality).
- Drug/Alcohol use criteria:
- Illicit drugs apart from cannabis or related products are prohibitive.
- Volunteers may consume caffeine, however, \>3 cups of coffee (or otherwise equivalent of \>300mg/day) is prohibitive.
- Participants who consume \>14 alcoholic drinks/week and/or have a diagnosis (or history) of alcohol use disorder will be excluded (a toxicological urine screen will be conducted to verify reported non-use during the initial screening and on the day of admission to the in-laboratory portion of the study).
- Use of prescription or over-the-counter medications or supplements that affect sleep are also exclusionary.
- Contraceptives are required for women and will continue to be taken throughout the experiment.
- Prior Shift Work:
- Volunteers must have no history of working irregular day and night hours, regular night work, or rotating shift work for the 3 months prior to the study.
Where
- Portland, Oregon
Related conditions & keywords
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 Oct 19, 2026 · Source of record for eligibility and locations