Adults initiating medical cannabis in Pennsylvania reported significant improvements in sleep quality within 3 months that were sustained through 12 months.
sleep researchers, medical cannabis patients, clinicians considering cannabis for sleep complaints
What the researchers found
Global sleep quality scores (PSQI) were significantly higher at baseline than at each follow-up point (p < 0.0001), with no significant differences among the 3-, 6-, 9-, and 12-month follow-ups, indicating early and sustained improvement. Benefits were seen across all PSQI subscales regardless of administration route or referring condition.
Why it matters
Poor sleep is one of the most common reasons people seek medical cannabis, but most evidence comes from short-term studies. This 12-month follow-up provides longer-term data on whether sleep improvements persist.
The numbers in context
137 participants followed for 12 months. Significant improvement in PSQI global scores at each follow-up vs. baseline (p < 0.0001). Improvements observed across all PSQI subscales. No differences by administration route (oral vs. other) or referring condition (chronic pain, anxiety, PTSD).
How the study worked
Prospective observational study of 137 adults newly referred for medical cannabis in Pennsylvania. Participants completed the Pittsburgh Sleep Quality Index at baseline and at 3, 6, 9, and 12 months. Linear mixed effects models assessed changes over time and whether route of administration or referring condition modified outcomes.
What this study cannot tell us
No control group or blinding. Self-reported sleep quality only, no objective sleep measures. Relatively small sample size (137). Potential selection bias from participants willing to complete multiple follow-ups. Products and doses were not standardized.
How to read the evidence
Prospective design with repeated measures and validated instrument strengthens findings, but lack of control group and reliance on self-report limit the evidence to moderate.
When this study was published
Recent prospective study from Pennsylvania's medical cannabis program.
The bigger picture
These findings add to growing evidence that medical cannabis may help with sleep, but the lack of a control group means improvements could reflect placebo effects, natural symptom fluctuation, or concurrent treatments.
Questions still open
- Would objective sleep measures like actigraphy confirm these self-reported improvements?
- Do sleep benefits persist beyond 12 months?
Common questions
Did the type of cannabis product matter?
Did the reason for using medical cannabis affect sleep outcomes?
Read the original research
Changes in sleep quality during the 12 months following medical cannabis initiation.
Journal of cannabis research, 7(1), 106
Citation
Short, Megan M; Lent, Michelle R; McCalmont, Thomas R; Dugosh, Karen L. (2025). Changes in sleep quality during the 12 months following medical cannabis initiation.. Journal of cannabis research, 7(1), 106. https://doi.org/10.1186/s42238-025-00376-7
Explore the wider topic
- Cannabis and Sleep: Does It Actually Help or Just Mask the Problem?
- How to Sleep Without Weed: 12 Methods That Actually Work
- Can You Take Melatonin During Weed Withdrawal?
- Nightmares After Quitting Weed: Why They Happen and When They Stop
- The Complete Sleep Recovery Timeline After Quitting Weed
- THC and REM Sleep Rebound: Why Your Dreams Go Wild When You Quit
- Weed Withdrawal Dreams: Why Your Dreams Are So Vivid and Intense
- Weed Withdrawal Insomnia: Why You Can't Sleep and What Actually Helps