Cannabis for Sleep: Small Benefit, Notable Side Effects

What Researchers Found About Sleep Disorders and Cannabis

Updated January 25, 2026Sleep, 2022

The Study at a Glance

Positive with Caveats

Published

Sleep, 2022

Researchers

Multiple institutions (International)

Study Type

Systematic Review

Participants

5,100 patients · Median 35 days

Key Finding

Medical cannabis and cannabinoids may improve impaired sleep among people living with chronic pain, but the magnitude of benefit is likely small.

Key Finding: Medical cannabis and cannabinoids may improve impaired sleep among people living with chronic pain, but the magnitude of benefit is likely small.

What Researchers Studied About Sleep Disorders and Cannabis

This was a systematic review to explore the effectiveness of medical cannabis for impaired sleep.

Researchers searched MEDLINE, EMBASE, CENTRAL, and PsychINFO to January 2021 for randomized trials.

39 trials (5100 patients) were eligible, with 38 evaluating oral cannabinoids and 1 evaluating inhaled cannabis.

How This Systematic Review Was Conducted

The median follow-up was 35 days.

Most trials (33 of 39) enrolled patients living with chronic cancer or non-cancer chronic pain.

The GRADE approach was used to appraise certainty of evidence. When possible, effect estimates were pooled for all sleep-related outcomes.

Sleep Disorders Treatment Results

The Main Results:

  • 1Sleep QUALITY (chronic pain): SMALL improvement vs placebo (RD 8%, 95% CI 3-12) - MODERATE certainty
  • 2Sleep DISTURBANCE (non-cancer pain): SMALL improvement (RD 19%, 95% CI 11-28) - moderate to high certainty
  • 3Sleep DISTURBANCE (cancer pain): VERY SMALL improvement (WMD -0.19 cm) - moderate to high certainty
  • 4DIZZINESS risk: SUBSTANTIAL increase (RD 29%, 95% CI 16-50) for trials 3+ months
  • 5SOMNOLENCE, dry mouth, fatigue, nausea: SMALL increase (RDs 6-10%)
  • 638 of 39 trials used oral cannabinoids
  • 7Median follow-up: 35 days

By the Numbers

StatisticWhat It Means
39 trialsNumber of randomized trials included (5100 patients total)
8% RDAdditional patients achieving meaningful sleep quality improvement vs placebo
29% RDIncreased risk of dizziness (substantial increase)
35 daysMedian follow-up duration across trials
39 trials

Number of randomized trials included (5100 patients total)

8% RD

Additional patients achieving meaningful sleep quality improvement vs placebo

29% RD

Increased risk of dizziness (substantial increase)

35 days

Median follow-up duration across trials

What This Means for Sleep Disorders Patients

If you have sleep problems related to chronic pain, this review has important findings.

The benefit is real but small: About 8% more patients achieve meaningful sleep quality improvement with cannabis compared to placebo. For sleep disturbance in non-cancer pain, 19% more patients improve.

Cancer patients see even smaller benefits for sleep disturbance (very small improvement).

But watch out for side effects: Dizziness risk increased substantially (29% more likely with cannabis). Sleepiness, dry mouth, fatigue, and nausea also increased (6-10% more likely each).

Important context: Most studies (33 of 39) were in patients with chronic pain. The sleep benefits may be secondary to pain relief rather than direct sleep effects.

The evidence quality is moderate to high for these findings, making them fairly reliable.

Quick Answers: Sleep Disorders and Cannabis

Direct answers based on the findings of this study:

Research Summary: Answers are based on published peer-reviewed studies and represent research findings, not medical recommendations. Individual results may vary. Always consult a healthcare provider before making treatment decisions.

Does medical marijuana help with sleep?

Small improvements for pain patients. A systematic review of 39 trials (5100 patients) found about 8% more achieve meaningful sleep quality improvement vs placebo. Non-cancer pain showed 19% improvement in sleep disturbance.

Source: AminiLari et al., Sleep, 2022 (PMID: 34546363)

What are the risks of using cannabis for sleep?

Dizziness is most common (29% more likely vs placebo). Somnolence, dry mouth, fatigue, and nausea also increased (6-10% each). A systematic review found benefits were small.

Source: AminiLari et al., Sleep, 2022 (PMID: 34546363)

What is the evidence for cannabis and sleep disorders?

Moderate to high certainty evidence from 39 trials shows cannabis provides small sleep improvements, primarily in chronic pain patients. Most evidence is for oral cannabinoids. Median follow-up was only 35 days. Side effects are notable.

Source: AminiLari et al., Sleep, 2022 (PMID: 34546363)

This is educational content, not medical advice

The research summarized here is for informational purposes only. Individual results may vary, and what works in studies may not work the same way for everyone. Always consult with a qualified healthcare provider before making changes to your treatment plan or starting medical cannabis therapy.

Important Limitations

This study has some caveats to keep in mind when interpreting the results:

  • Most patients had chronic pain (not primary sleep disorders)
  • Median follow-up only 35 days
  • Only 1 trial evaluated inhaled cannabis
  • Sleep benefits may be secondary to pain relief
  • Notable side effect profile (especially dizziness)

The Bottom Line on Cannabis for Sleep Disorders

This systematic review of 39 trials (5100 patients) found cannabis provides small sleep improvements for chronic pain patients (8% more achieve meaningful improvement). Non-cancer pain patients showed 19% improvement in sleep disturbance. However, side effects are common: dizziness (29% increased risk), plus somnolence, dry mouth, fatigue, and nausea (6-10% each). Benefit is real but small.

Do You Qualify for Medical Marijuana?

If you're living with Sleep Disorders, you may qualify for a medical marijuana card. Our licensed physicians can evaluate you from home via telehealth.

Related Research & Resources

Source

AminiLari M, Wang L, Neumark S, et al. "Medical cannabis and cannabinoids for impaired sleep: a systematic review and meta-analysis of randomized clinical trials" Sleep. 2022. DOI: 10.1093/sleep/zsab234

Study information sourced from PubMed®, U.S. National Library of Medicine.

Medically Reviewed By

MMJ.com Medical Advisory Board

Last Updated: January 25, 2026

Important Information

Not Medical Advice: This research summary is for educational purposes only. It should not be used to diagnose, treat, cure, or prevent any disease or medical condition. Always consult a qualified healthcare provider before starting or changing any treatment.

Individual Variation: Research findings represent group averages. Your individual response to cannabis may differ based on genetics, other medications, underlying conditions, and many other factors.

Last reviewed: January 25, 2026

Important Notices

Research Summary Disclaimer

This content represents our interpretation of published scientific research for educational purposes. It should not be used to make treatment decisions without consulting a qualified healthcare provider. Individual results may vary from study findings.

FDA Notice

These statements have not been evaluated by the FDA. Cannabis is not intended to diagnose, treat, cure, or prevent any disease. The FDA has not approved cannabis for any medical condition except specific prescription medications.

Copyright & Fair Use

Research summaries are provided under fair use (17 U.S.C. § 107) for educational purposes. We provide brief summaries with attribution, not full reproductions. All studies remain the intellectual property of their respective authors and publishers.

Data Sources

Study information sourced from PubMed®, U.S. National Library of Medicine. Inclusion does not imply endorsement by NLM, NIH, or the federal government.

For complete information, see our Terms of Use and Research Content Policy.

FAQs: Cannabis for Sleep Disorders

Does cannabis help sleep?

Yes, but the benefit is small. A systematic review of 39 trials found 8% more chronic pain patients achieve meaningful sleep quality improvement with cannabis vs placebo. Non-cancer pain patients showed 19% improvement in sleep disturbance.

What are the side effects of cannabis for sleep?

Side effects are common. This review found dizziness risk increased substantially (29% more likely). Somnolence, dry mouth, fatigue, and nausea also increased (6-10% each).

Is cannabis good for insomnia?

Evidence is limited. Most studies (33 of 39) were in chronic pain patients, not primary insomnia. Sleep benefits may be secondary to pain relief. The magnitude of direct sleep benefit is likely small.