Quick Summary
A 2026 Cochrane review of nine clinical trials involving 537 adults found that medical cannabis may have little to no clinically meaningful benefit for sleep quality, sleep duration or daytime functioning.
Medical cannabis was associated with more unwanted side effects than placebo. Known side effects of medical cannabis include dizziness, dry mouth and fatigue.
The evidence remains uncertain because studies were small, short and tested different cannabis products. Medical cannabis is not currently recommended as a treatment for chronic insomnia.
Medicinal Cannabis For Sleep
Medical cannabis is becoming an increasingly popular option for people struggling with insomnia. For someone who has spent months or even years lying awake at night, the possibility of a treatment that makes falling or staying asleep easier is understandably appealing.
Many people who use cannabis report that it helps them sleep. But personal experiences and scientific evidence do not always tell the same story. Feeling sleepier after taking something does not necessarily mean you will sleep better, sleep longer or feel more refreshed the following day. So does medical cannabis actually improve sleep?
To get a better understanding of the relationship between medicinal cannabis and sleep difficulties, researchers published a major Cochrane systematic review in October 2026. The review, a type of study that gathers and combines all the trials on a question, examined whether medical cannabis actually helps people with insomnia (Varela et al., 2026).
The findings raise important questions about how effective medicinal cannabis products really are, particularly when their potential benefits are weighed against their side effects.
So before examining the results, what is medical cannabis, and how might its different ingredients affect sleep?
What Is Medical Cannabis, and How Do THC and CBD Differ?
Medical cannabis refers to cannabis-derived products used for therapeutic purposes. Medicinal cannabis products contain compounds called cannabinoids, which interact with the body’s endocannabinoid system, a network of chemical signals involved in regulating functions such as mood, appetite, pain and sleep.
The two best-known cannabinoids are:
Tetrahydrocannabinol (THC): The main psychoactive compound in cannabis, responsible for the characteristic “high”. THC can produce feelings of relaxation and sleepiness, although its effects vary between individuals.
Cannabidiol (CBD): A cannabinoid that does not produce the intoxicating high associated with THC. CBD has attracted considerable interest for its potential effects on anxiety, relaxation and sleep.
Medical cannabis products come in several forms, including oils, capsules and pharmaceutical preparations. Some contain THC, others contain CBD, and many contain combinations of the two.
Understanding exactly what is in a medical cannabis product is important because THC and CBD act on the body in different ways. And a finding about one cannabis product does not necessarily apply to another.
Although the endocannabinoid system is involved in sleep regulation, that alone doesn’t establish that taking cannabis will improve sleep or insomnia.
So what happens when researchers actually test these products against a placebo?
Does Medical Cannabis Improve Sleep Quality?
Medical cannabis may have little to no clinically meaningful effect (i.e. a change large enough for patients to notice) on sleep quality or satisfaction with sleep, according to Varela and colleagues’ review (2026) .
Varela et al. (2026) reviewed nine randomized controlled trials, studies in which participants are assigned by chance to one treatment or another, involving 537 adults with insomnia. These studies compared medical cannabis with a placebo (an inactive dummy treatment) or another medication, allowing researchers to investigate whether any improvements were attributable to the medical cannabis treatment itself.
Seven trials, involving 374 participants, examined sleep quality or satisfaction with sleep. When the researchers combined the results, they found no convincing evidence that medical cannabis produced a clinically meaningful improvement compared with placebo.
It’s worth noting that there was considerable disagreement between the individual studies. Some reported improvements in sleep quality, while others found little difference.
One particularly informative study was the CAN-REST trial, which tested CBD against placebo in more than 200 adults over eight weeks. Despite being considerably larger than most of the other trials, it found no significant improvement in insomnia symptoms with CBD (Hoyos et al., 2024).
So the available research hasn’t established that cannabis products reliably improve sleep quality in people with insomnia. But sleep quality is only one part of the picture. Could cannabis still help people fall asleep faster or spend more time asleep?
Does Medical Cannabis Help You Fall Asleep Faster or Sleep Longer?
Varela and colleagues (2026) found that medical cannabis didn’t demonstrate a reliable improvement in either sleep duration or the time it takes to fall asleep.
One advantage of the Cochrane review (Varela et al., 2026) was that it examined studies using objective sleep measurements, rather than relying entirely on participants’ recollections. These measurements included polysomnography, an overnight sleep study that records brain activity and other physiological signals, and actigraphy, which uses wearable movement sensors to estimate sleep and wakefulness.
Across six trials involving 194 participants, the researchers found that people taking medical cannabis slept an average of approximately eight minutes longer than those taking a placebo (Varela et al., 2026).
Eight minutes is, of course, a very small difference. But importantly, the results were highly uncertain.
Varela et al., (2026) reported that the statistical range of plausible effects extended from approximately 23 minutes less sleep to 38 minutes more sleep per night. In other words, the studies couldn’t reliably establish whether cannabis increases sleep duration, makes little difference or even reduces it.
The Cochrane researchers also examined two common difficulties experienced by people with insomnia:
Sleep onset latency: The time it takes to fall asleep after attempting to sleep.
Wake after sleep onset: The total time spent awake during the night after initially falling asleep.
For both sleep onset and wake after sleep measures, the average difference between medical cannabis and placebo was less than five minutes.
So current evidence suggests that cannabis doesn’t consistently improve the amount or continuity of sleep. However, the reason people seek treatment for insomnia is not simply to accumulate more minutes of sleep. They also want to feel better during the day. So can medical cannabis help with that?
Does Medical Cannabis Improve Daytime Functioning or Quality of Life?
Medical cannabis did not show a clear benefit for daytime functioning, although there was some preliminary evidence that it may improve general well-being (Varela et al., 2026).
The Cochrane review examined five trials involving 144 participants that measured daytime functioning, including sleepiness and alertness. The combined results suggested little to no clinically meaningful improvement compared with placebo (Varela et al., 2026).
The Cochrane researchers also examined quality of life, a broader measure that includes physical health, emotional well-being and satisfaction with daily activities. Three trials involving 95 participants suggested that medical cannabis might improve quality of life. However, the evidence was rated as very low certainty, meaning the true effect remains unclear.
One small Australian trial helps illustrate this distinction. Narayan et al. (2024) compared nightly CBD with placebo in 30 adults with insomnia. Participants taking CBD reported improvements in well-being, despite showing no significant improvement in most measures of insomnia or sleep.
So it is possible, therefore, that some people experience benefits from CBD that are not directly related to improved sleep. But the strength of the evidence isn’t strong.
When thinking about benefits it’s also worth considering: how does any potential benefit from taking a medicinal cannabis product weigh against the possibility of unwanted side effects?
What Are the Side Effects of Medical Cannabis for Sleep?
Medical cannabis was associated with more unwanted side effects than placebo in the trials examined by the Cochrane review (Varela et al., 2026).
Three crossover trials involving 98 participants provided particularly useful information. In these studies, participants received both cannabis and placebo at different times, allowing researchers to compare their experiences under each condition.
The findings from the 98 participants were striking:
No participants experienced side effects only while taking placebo.
37 participants experienced side effects only while taking medical cannabis.
14 participants experienced side effects during both treatment periods.
47 participants experienced no side effects during either period.
The pooled analysis, which combined the results of these three trials, found substantially higher odds of reporting an adverse event while taking cannabis (Varela et al., 2026).
Potential side effects can include dizziness, dry mouth, tiredness, memory difficulties, increased appetite and feelings of stress or worry.
It’s worth pointing out that these side effects deserve particular attention when treating insomnia. Someone already struggling with daytime fatigue, concentration or alertness may find that unwanted medicinal cannabis effects add to those difficulties.
There is also the question of long-term safety. The trials in the Cochrane review were relatively short, with follow-up extending no longer than 12 weeks. That leaves important questions about sustained effectiveness, tolerance, dependence and withdrawal unanswered.
Only one small trial specifically examined withdrawal symptoms after stopping treatment (Ried et al., 2023). Although none were identified, the study involved just 34 participants, far too few to establish long-term safety (Varela et al., 2026). And see our clinical comment below on what wasn’t in the review.
Given these findings, why do so many people report that cannabis helps them sleep?
Why Do So Many People Say Cannabis Helps Their Sleep?
Many people report sleeping better after starting medical cannabis, but without a placebo to compare to, that improvement does not necessarily establish that cannabis was responsible.
For example, a Canadian retrospective chart review, a look back through patients’ existing medical records, found that many patients with follow-up information reported improvements in sleep or a related condition after using medical cannabis (Vaillancourt et al., 2022). Findings like these help explain why cannabis has developed a reputation as a sleep aid.
However, observational studies have an important limitation: without a suitable comparison group, researchers cannot confidently determine what caused the improvement.
Sleep naturally varies from night to night. Expectations about a treatment can influence how people experience and report their sleep and placebo effects are notoriously strong in insomnia studies. Other symptoms, such as pain or anxiety, may also change during treatment.
There is also a difference between feeling sedated and obtaining better sleep. A substance that makes someone feel relaxed or sleepy may seem helpful, even if it does not substantially change their sleep duration, continuity or next-day functioning.
That’s not to say people’s experiences aren’t important. It’s simply that randomized controlled trials are better equipped to establish whether the treatment itself produced the improvement.
So how confident should we be in what the clinical trials have found so far?
How Reliable Is the Research on Cannabis and Insomnia?
The current evidence is limited, and the Cochrane researchers rated their confidence in the findings as low or very low across all measured outcomes.
Several problems contributed to this assessment and are, more generally, limits of many cannabis product studies:
First, most studies were small. Many included fewer than 50 participants. Small trials produce less precise estimates and may not accurately represent how a treatment performs across a broader population.
Second, the studies were short. Chronic insomnia is a condition involving sleep difficulties occurring at least three times a week for three months or longer. Trials lasting only a few nights or weeks cannot establish whether a treatment remains effective over months or years.
Third, the cannabis products differed substantially. Some studies examined CBD, others THC or combinations of cannabinoids. Doses and formulations varied, making it difficult to determine whether particular products are more effective than others.
Fourth, several studies had methodological limitations. Only two of the nine trials were judged to be at low risk of bias, meaning the results of the remaining studies were more vulnerable to errors arising from how the research was conducted or analyzed.
Finally, the participants were not fully representative of everyone experiencing insomnia. Women accounted for a large majority of participants, and older adults and people with other health conditions were underrepresented.
The Cochrane review also provided little useful evidence comparing medical cannabis directly with established insomnia treatments.
So, overall, the research does not establish that medical cannabis is ineffective per se. It establishes that we currently lack sufficiently reliable evidence to recommend it as an effective treatment for insomnia.
What Is the Recommended Treatment for Chronic Insomnia?
Cognitive behavioral therapy for insomnia (CBT-I) remains the recommended first-line treatment for chronic insomnia, rather than medical cannabis.
Clinical guidelines from the American College of Physicians and European sleep experts recommend CBT-I because its effectiveness has been established through controlled clinical research (Qaseem et al., 2016; Riemann et al., 2023).
Unlike treatments that primarily aim to produce sedation, CBT-I addresses the psychological, behavioral and physiological processes that contribute to persistent insomnia. These processes include changes in sleep regulation, learned associations between bedtime and wakefulness, and the patterns of thinking and behavior that can maintain sleep difficulties long after the original trigger has passed.
Medication can also have a role in insomnia treatment, depending on individual circumstances. However, none of the major insomnia guidelines recommend medical cannabis as an established treatment.
For someone considering cannabis specifically to improve their sleep, the current evidence provides good reason to be cautious, particularly given the uncertain benefits and potential for side effects. There is also no long term evidence on the development of tolerance or how easy it is to discontinue medical cannabis.
Before considering the next steps, what might a systematic review miss about the original studies behind it?
Clinical Comment: What Can a Systematic Review Miss?
Systematic reviews provide an important overview of the scientific evidence, but some clinically relevant details in the original trials may not appear in a review’s headline conclusions or may be left out because of how the review was designed. So we always suggest looking closer at the individual studies that make up some of these reviews, especially when there are very few studies making up a review, or the studies are flagged as having a risk of bias.
A good example is the Thai trial by Aiewtrakoon (2024) that was included in the Cochrane review. It contributed one of the more positive results to the Cochrane review: Clinical Comment: What Can a Systematic Review Miss?
Systematic reviews provide an important overview of the scientific evidence, but some clinically relevant details in the original trials may not appear in a review’s headline conclusions or may be left out because of how the review was designed. So we believe it is important to look closer at the individual studies that make up some of these reviews, especially when there are very few studies making up a review, or the studies are flagged as having a risk of bias.
The Thai trial by Aiewtrakoon (2024) that was included in the Cochrane review provides an example. It contributed one of the more positive results to the Cochrane review: participants taking CBD slept approximately 57 minutes longer than those taking placebo. Yet the Cochrane review did not mention that the paper also reported that 33 participants (described as 73% of those enrolled) experienced difficulty sleeping after CBD was discontinued. According to the study, these participants were reviewed at the medical cannabis clinic within two weeks and referred to a psychiatric department for further treatment.
The Thai trial (Aiewtrakoon, 2024) did not provide the detailed post-discontinuation measurements needed to determine whether this was a return of the original insomnia, rebound insomnia (sleep becoming worse than before treatment once it stops) or a withdrawal effect. But it raises a clinically important question about whether improvements persist when treatment stops. It’s probably safe to say that a treatment that leaves you with side-effects requiring further treatment elsewhere is not what most insomnia sufferers are looking for.
This observation doesn’t invalidate the Cochrane review’s conclusions. But it illustrates why pooled statistics and original research sometimes need to be read together. Whether a treatment helps while it is taken is important, but so is what happens to patients when it is stopped.
So where does that leave someone who is still struggling to sleep?
Where To From Here?
Persistent insomnia can be exhausting, particularly when you have already tried different treatments without lasting success. It is understandable that medical cannabis might seem appealing, especially when other people describe positive experiences.
However, the latest research does not yet provide convincing evidence that cannabis offers a reliable solution for chronic insomnia.
The encouraging news is that insomnia is a well-understood and treatable condition. Effective treatment does not depend on finding a substance that makes you sleepy.
Working with a Behavioral Sleep Medicine specialist provides an opportunity to understand the particular factors maintaining your sleep difficulties and develop a structured, individualized treatment program. Rather than relying on temporary sedation or generic sleep advice, the aim is to address the underlying mechanisms of insomnia and achieve sustainable improvements in both sleep and daytime functioning.
Frequently Asked Questions About Medical Cannabis for Insomnia
Q1: Does medical cannabis help with insomnia?
A1: Medical cannabis may have little to no clinically meaningful benefit for insomnia, according to a 2026 Cochrane review of nine randomized controlled trials involving 537 adults (Varela et al., 2026). Compared with placebo, medical cannabis did not clearly improve sleep quality, sleep duration or daytime functioning. The researchers rated their confidence in these findings as low or very low, so a benefit cannot be ruled out.
Q2: Does CBD help you sleep?
A2: CBD has not been shown to reliably improve sleep in people with insomnia. The CAN-REST trial, which tested CBD against placebo in more than 200 adults over eight weeks, found no significant improvement in insomnia symptoms (Hoyos et al., 2024). A smaller Australian trial found that CBD improved well-being but not most measures of insomnia or sleep (Narayan et al., 2024).
Q3: How much longer do people sleep on medical cannabis?
A3: People taking medical cannabis slept about eight minutes longer per night on average than those taking placebo, across six trials that measured sleep with overnight sleep studies or wearable movement sensors (Varela et al., 2026). The plausible range ran from about 23 minutes less sleep to 38 minutes more. The studies therefore could not establish whether cannabis increases sleep, makes little difference or reduces it.
Q4: What are the side effects of using medical cannabis for sleep?
A4: Medical cannabis caused more unwanted side effects than placebo in the trials reviewed by Varela et al. (2026). In three crossover trials involving 98 participants, 37 people had side effects only while taking cannabis, and no one had side effects only while taking placebo. Known side effects of medical cannabis include dizziness, dry mouth, tiredness, memory difficulties, increased appetite and feelings of stress or worry.
Q5: Why do people say cannabis helps them sleep if the trials show little benefit?
A5: Reports of better sleep on cannabis come mostly from studies without a comparison group. In a Canadian retrospective chart review, many patients with follow-up information reported improvements in sleep or a related condition after using medical cannabis (Vaillancourt et al., 2022). Without a placebo group, natural night-to-night changes in sleep, expectations and changes in pain or anxiety cannot be separated from the effect of cannabis. Feeling sedated is also not the same as sleeping better.
Q6: Can stopping CBD cause sleep problems?
A6: Stopping CBD may be followed by sleep difficulties, although the evidence is limited. In a Thai trial included in the Cochrane review by Varela et al. (2026), 33 participants (73% of those enrolled) had difficulty sleeping after CBD was discontinued (Aiewtrakoon, 2024). The trial did not report enough detail to tell whether this was the original insomnia returning, rebound insomnia or a withdrawal effect. The only trial that measured withdrawal symptoms directly found none, but it involved just 34 participants (Ried et al., 2023).
Q7: Is medical cannabis recommended for chronic insomnia?
A7: Cognitive behavioral therapy for insomnia (CBT-I) is the recommended first-line treatment for chronic insomnia, according to guidelines from the American College of Physicians and European sleep experts (Qaseem et al., 2016; Riemann et al., 2023). None of the major insomnia guidelines recommend medical cannabis as an established treatment. CBT-I targets the changes in sleep regulation, learned bedtime associations and patterns of thinking and behavior that keep insomnia going.
References
Aiewtrakoon, C. (2024). Efficacy and safety of cannabidiol oil on chronic insomnia: The first randomized, double-blind, placebo-controlled, crossover, pilot study in Thailand. Journal of the Medical Association of Thailand, 107(3), 160–170. https://doi.org/10.35755/jmedassocthai.2024.3.13952
Hoyos, C., Marshall, N., Gordon, C., Yee, B., McGregor, I., & Grunstein, R. R. (2024). The cannabidiol use for relief of short-term insomnia (CAN-REST): A randomised placebo-controlled clinical trial [Abstract]. Sleep, 47(Suppl. 1), A169–A170. https://doi.org/10.1093/sleep/zsae067.0394
Narayan, A. J., Downey, L. A., Rose, S., Di Natale, L., & Hayley, A. C. (2024). Cannabidiol for moderate-severe insomnia: A randomized controlled pilot trial of 150 mg of nightly dosing. Journal of Clinical Sleep Medicine, 20(5), 753–763. https://doi.org/10.5664/jcsm.10998
Qaseem, A., Kansagara, D., Forciea, M. A., Cooke, M., Denberg, T. D., & Clinical Guidelines Committee of the American College of Physicians. (2016). Management of chronic insomnia disorder in adults: A clinical practice guideline from the American College of Physicians. Annals of Internal Medicine, 165(2), 125–133. https://doi.org/10.7326/M15-2175
Ried, K., Tamanna, T., Matthews, S., & Sali, A. (2023). Medicinal cannabis improves sleep in adults with insomnia: A randomised double-blind placebo-controlled crossover study. Journal of Sleep Research, 32(3), e13793. https://doi.org/10.1111/jsr.13793
Riemann, D., Espie, C. A., Altena, E., Arnardottir, E. S., Baglioni, C., Bassetti, C. L. A., Bastien, C., Berzina, N., Bjorvatn, B., Dikeos, D., Dolenc Groselj, L., Ellis, J. G., Garcia-Borreguero, D., Geoffroy, P. A., Gjerstad, M., Gonçalves, M., Hertenstein, E., Hoedlmoser, K., Hion, T., … Spiegelhalder, K. (2023). The European Insomnia Guideline: An update on the diagnosis and treatment of insomnia 2023. Journal of Sleep Research, 32(6), e14035. https://doi.org/10.1111/jsr.14035
Suranaree University of Technology. (2021, May 7). SUT partners with the private sector to develop an integrated cannabis production chain [University news announcement, in Thai]. https://www.sut.ac.th/news/detail/4/news20210503
Vaillancourt, R., Gallagher, S., Cameron, J. D., & Dhalla, R. (2022). Cannabis use in patients with insomnia and sleep disorders: Retrospective chart review. Canadian Pharmacists Journal, 155(3), 175–180. https://doi.org/10.1177/17151635221089617
Varela, L. B., Miño Zambrano, J. E., Maura Goncalves Costa, B., Santos Marques da Silva, G., Escobar Liquitay, C. M., Díaz Menai, S., Meza, N., & Garegnani, L. I. (2026). Medical cannabis for the treatment of insomnia. Cochrane Database of Systematic Reviews, 2026(10), CD016216. https://doi.org/10.1002/14651858.CD016216.pub2
Written By Dan Ford, DBSM, Sleep Psychologist
Published By The Better Sleep Clinic
