Decoding Cannabis: Can cannabinoids help you sleep better?

Few things are as universally human, or as annoyingly elusive, as sleep can be (at least for most people, some of the time). 

A third of our entire life is supposed to be spent tucked up nice and snug, but for millions of us, sleep remains a nightly struggle. Sleeping pills don’t always work, and some come with a list of potential side effects that are what nightmares are made of. 

And that crucial time of day, when we’re meant to be winding down, switching off, letting go, becomes a trigger for that underlying anxiety of “what if I just can’t fall asleep again tonight?” 

The more we try to force it, the further it drifts. Sleep becomes something chased, but rarely caught. A catch-22 indeed. 

Welcome to the third June 2025 edition of Decoding Cannabis, a series that unpacks the science of medical cannabis to be more accessible for medical cannabis patients. Today, we are focusing on what the research says about cannabinoids and sleep, specifically, a 2021 clinical review titled “Effects of Cannabinoids on Sleep and Their Therapeutic Potential for Sleep Disorders”. 

It pulls together dozens of studies on THC, CBD, and other cannabinoids to explore a simple question, one that many people feel they already know the answer to: 

“Can cannabis actually help us sleep better?”

We’ve seen a huge uptick in interest surrounding medical cannabis prescriptions for insomnia and other sleep disorders, and with interest rising in natural alternatives to sleeping pills, especially here in the UK, it’s a question worth fully dissecting. 

Can’t sleep? Here’s what might help (besides pills)

Struggling to fall asleep, or to get a full seven to eight hours, is one of the most common health complaints in the UK. It’s safe to say that everyone old enough to be reading these words has, at some point, faced the slow torture of a night that just won’t end. 

Maybe your mind refuses to slow down. Maybe you're pushing through heavy body aches. Or maybe there’s no clear reason at all. Just the quiet dread of another bleary morning inching closer with every glance at the clock.

But ask most people who’ve gone through the rigmarole of the usual pharmaceutical options, things like benzodiazepines (Xanax and Valium) or sleep meds like Zopiclone (the ones doctors hand out when nothing else seems to do the trick), and the story is often the same. They work for a while, then often, they stop meeting the mark. Or they leave you feeling sluggish and foggy the next day. Or worse….

What are the most common causes of poor sleep?

The general stress of life, chronic pain, mental health concerns like anxiety and depression are major culprits, but simple day-to-day issues like noise, light, temperature, or an overactive mind can be just as disruptive. And then there are the nights when nothing seems wrong, yet you still can’t drift off.

Plenty of people live with long-term sleep disruption and never get a clear answer as to why they are struggling. Standard treatment often skims over these deeper causes, handing out sleeping pills while the underlying problem goes unaddressed.

Do pharmaceutical sleep aids work long term?

Most sleep aids don’t fix the root of the problem. They sedate, which can help you fall asleep, but they don’t tend to improve sleep quality for most. They might make you feel ‘knocked out’, but not well rested. Over time, for many, even that wears off.

Drugs like Zopiclone do often bring short-term relief, but they also carry the risk of dependence, tolerance, and that groggy morning-after feeling. So, it’s no surprise that so many people are now looking for natural alternatives to sleeping tablets. They want something gentler, more sustainable, and capable of supporting proper, restorative sleep.

What the research says about taking medical cannabis for sleep disorders (insomnia, PTSD, obstructive sleep apnoea, and restless leg syndrome)

The 2021 review looked at over 30 studies that covered conditions including insomnia, PTSD, obstructive sleep apnoea (OSA), and restless leg syndrome (RLS). The findings were mixed, but most suggested clear short-term benefits, particularly when sleep problems were linked to other diagnoses.

When we look at medical cannabis for sleep in the UK and beyond, the strongest evidence comes from studies where poor sleep is secondary to chronic pain, anxiety, or trauma. In these cases, cannabinoids may help more than just sedation by addressing the root cause of disrupted rest.

Can medical cannabis help with chronic insomnia?

Several studies in the review found that medical cannabis for insomnia reduced sleep latency and led to fewer nighttime awakenings. In other words, patients fell asleep faster and woke less often, at least over the short term.

The most consistent benefits appeared in patients who also experienced anxiety or chronic pain. Some trials used synthetic THC like Dronabinol or Nabilone and showed similar effects. 

The authors concluded that cannabis administration may be most helpful for people whose insomnia is part of a wider health picture.

Does cannabis improve sleep for PTSD, obstructive sleep apnoea, or restless leg syndrome?

In PTSD, the link is clearest.

Several studies found that cannabis-based medicines reduced the frequency and intensity of nightmares. It didn’t just help with falling asleep, but also with staying asleep and waking less distressed. Sleep felt more manageable, even when other treatments had failed.

For sleep apnoea, early data suggest some potential.

A phase II placebo-controlled trial found that Dronabinol reduced the Apnea-Hypopnea Index and lowered subjective sleepiness in patients with obstructive sleep apnoea. Animal studies also showed that THC stabilised breathing patterns and reduced apnoea episodes, possibly due to its effects on vagal nerve regulation. 

Restless legs syndrome has been less studied. 

Two small case series (one with six patients, another with twelve) reported near-total remission of symptoms after using cannabis in a recreational setting, alongside their usual medications. However, there were no control groups, and no polysomnography data were collected.

Keep in mind that these studies were small, and while very promising, long-term outcomes remain unknown.

Cannabis may improve sleep by easing pain and anxiety

Most people don’t have sleep problems in a vacuum. We have mentioned this a few times already, but the evidence does seem to point to the fact that cannabis-based treatment options seem to be best applied when something else is getting in the way.

Cannabis doesn’t force sleep. What it seems to do, at least for some people, is take the edge off pain and anxiety. When both the body and the mind stop bracing for an onslaught, sleep gets a real shot.

We won’t go into the endocannabinoid system here, but if you want a clear explanation of how it works, you can head over to the quick explainer ”What is the endocannabinoid system?”

Can cannabis improve sleep by reducing pain and anxiety?

A number of the studies mentioned in this review show the same pattern. When pain levels drop, sleep increases. People with conditions like fibromyalgia and other long-term injuries slept better when their pain was being properly managed, in these instances, especially with THC or synthetic options like Nabilone.

And that makes sense. The same system (the ECS among others) that controls pain also affects sleep, and CB1 receptors sit right in the middle of it. When those are activated, the body calms down. Not in a numbed, sedated way, but in a way that feels safe enough to rest in.

The section above where we discussed medical cannabis for PTSD showed a similar pattern for anxiety issues. When anxiety symptoms eased, sleep improved as a result. Patients using cannabinoids like Nabilone reported fewer nightmares, less hypervigilance and more consistent rest.

How CBD helps you sleep and when it works best

While CBD oil and CBD sleep specific products are widely available over the counter in the UK, they are not all created equal. In medical cannabis treatment, CBD is used in higher concentrations and prescribed under clinical supervision. 

Store-bought, also known as OTC (over the counter) options are simply not subject to the same level of regulatory oversight as medical cannabis products in the UK, and come with zero clinical guidance. 

Does CBD reduce anxiety enough to help you sleep?

For some people, yes. The studies suggest that when anxiety goes down, sleep often improves. That’s where CBD can make a difference, not by sedating you, but by turning the volume down on whatever’s keeping your mind too active to rest. 

It seems to be especially helpful for people who struggle to sleep because of stress, panic or that wired-but-tired feeling.

One fascinating and frequently cited large scale study (that was not included in the review) found that CBD reduced anxiety in 79% of patients within the first month, with 67% also reporting improved sleep.

When is CBD most effective for sleep?

Evening dosing seems to work best, typically one to two hours before bed. Capsules and oils take longer to kick in, but can last through the night. If someone’s issue is middle-of-the-night waking, sublingual drops or a quick vape may be a better fit. It’s about matching the format to the pattern of disrupted sleep.

What are the safety and side effects of CBD for sleep?

The side effects of CBD are usually mild, most often a dry mouth, low energy, or an unsettled stomach. 

But even at higher doses, CBD isn’t addictive and doesn’t lead to withdrawal. Medical CBD in the UK is tightly controlled for quality and dosage, which makes it more reliable than many of the high-street or over-the-counter options now available. 

All Releaf prescriptions come through our world-class clinical team and are individualised to each patient’s needs. That includes careful monitoring, support, and dosing adjustments, something over-the-counter products simply can’t offer. 

Does medical cannabis help you sleep better? What patients are saying…

There is no substitute for clinical trials and peer-reviewed data, but real-world patient experiences regularly prove how the science plays out in practice. 

At Releaf, we hear from patients who’ve turned to medical cannabis after years of poor sleep, unwanted side effects from prescription meds, or a sense that nothing else was really working for their health concerns or needs. 

A quick look through the long list of Releaf patient success stories shows that almost every single one mentions some improvement in sleep, whether it’s falling asleep faster, staying asleep longer, or waking up feeling more rested.

For many, sleep wasn’t even the main reason they sought treatment, but it quickly became one of the most noticeable changes. Patients living with anxiety, chronic pain, PTSD, or menopause symptoms often describe better sleep as a welcome side effect of managing those underlying issues more effectively with cannabis.

These stories don’t replace clinical evidence, but they do reflect something important: when treatment is personalised and clinically guided, sleep may stop being a nightly battle.

If you would like to learn more about how medical cannabis may help you find a more restful sleep schedule, feel free to head over to our fast and free medical cannabis eligibility checker. It takes less than 20 seconds to complete.