Cannabinoid use has been associated with many positive effects on health. From various neurological conditions, to vascular disorders, glaucoma, chronic pain, Tourette Syndrome, and psychosis, everything has been treated with Cannabis (C. sativa or C. indica), since ancient times.
There certainly seems to be some scientific proof regarding many of these anecdotal effects. Science is still too shaky for the most part on most of these alleged effects though. What we know thus far, definitely warrants further scientifically substantiated studies, supported by more solid methodology.
To understand the current state of science regarding the two major active constituents of cannabis and their effect on sleep as well as on various health conditions, we need to take a comprehensive look at the active ingredients of the herb. Recent scientific findings regarding the effects of these ingredients as well as breakthroughs in synthetic cannabinoids need to be considered as well.
The active constituents of Cannabis
The actual composition of cannabis is nowhere nearly as simple as a quick glance over the issue would have you believe. There are scores of chemicals involved that science has thus far managed to identify and isolate. There are probably scores more that are still unknown. Such complex constituent profiles complicate the issue of understanding the effect every individual compound exerts, on account of the synergistic nature of the whole.
That said, for the scope of this article, considering the two main constituents is sufficient.
Delta-9 tetrahydrocanabinol (THC) is the “euphoria” ingredient. Responsible for the “high” experienced by marijuana users, THC provides a number of benefits health-wise. It is however also responsible for almost all the undesired side effects of cannabinoid use, such as cognitive impairment, panic attacks, psychosis etc.
Cannabidiol (CBD), on the other hand, is a non-intoxicating constituent, which is almost side effect-free. It also has beneficial effects, without the problems caused by THC. What’s more, it even counters some of the negative effects of THC, so in some cases, using the two compounds together makes perfect sense.
By What Mechanism do CBD and THC Act?
The general area targeted by phytocannabinoid (plant-based cannabinoid) use is obviously the brain. Within it, the endocannabinoid system (ECS) is the “landing site” of compounds such as THC and CBD.
The ECS can be loosely defined as a collection of receptors and neuromodulatory lipids, located in the brain as well as in the central and peripheral nervous system. That explains the effects that cannabinoids elicit in users and why they are so efficient at eliciting these effects.
The primary receptors of the ECS are CB1 and CB2. There are obviously scores of other receptors involved, like GPR55, TRPM8, TRPA1 etc. For the scope of this article, which is restricted to THC and CBD, we only really need to acknowledge the presence of CB1 and CB2.
THC acts on CB1, while CBD acts on CB2. Again: this is a very simplified look at the overall picture, but it does not skew it. It is also much easier to comprehend. In fact both compounds act on multiple receptors.
Synthetic Cannabinoids and Their Role
While marijuana use is on the rise, medical applications of the plant still continue to carry a sort of stigma. That said, there are synthetic derivatives out there, which have been used clinically for quite some time.
In regards to THC, such synthetic derivatives/extracts are dronabinole and nabilone. CBD has been isolated under the same name. Another interesting extract is Sativex, which is a THC/CBD 1:1 concoction.
As mentioned, many of these extracts are already used clinically. Some of them are prescribed for PTSD, others alleviate nausea/vomiting in cancer-related chemotherapy.
They also allow researchers to study the effects of the isolated compounds and thus to learn how specific cannobinoids act. Such research – though just a small part of the bigger picture – is essential for the eventual understanding of the full mechanisms through which these compounds elicit their effects.
The Endocannabinoid System
As mentioned, both THC and CBD act on the receptors of the ECS. The Endocannabinoid system is still a relatively poorly understood part of human biology.
What is known about it however, explains many of the health-wise positive effects of cannabinoids. The ECS has for instance been linked to the Circadian Sleep-Wake Cycle. Thus, it has a hand in the triggering, promotion and maintenance of sleep.
By acting on some of the above mentioned receptors, cannabinoids exert an effect on sleep. The ECS is also involved in the release of opioid peptides, which explains the role of cannabinoids in the management of chronic pain.
The Therapeutic Effects of Cannabinoids
While the focus of the article is on the sleep-related benefits of CBD and THC, the potential therapeutic applications of these compounds span a much wider range.
Various neurological conditions, such as: muscle spasms and multiple sclerosis, Parkinson’s Disease, pain management (chronic pain relief too), Tourette’s syndrome, head injuries, psychosis and neurosis.
- Cardiovascular diseases
- The stimulation of appetite
- Antiemetic benefits (for chemotherapy patients)
- Sleep improvement
Cannabinoids and Sleep
The effects of cannabis on sleep have been studied since the 1970s. Early studies often yielded contradictory results. In hindsight, the contradictory nature of some of the findings could probably be written down to the use of plant cannabis rather than isolated cannabinoids in the studies.
Despite the erratic nature of the findings, some conclusions could be drawn. It was observed that cannabis influenced sleep onset latency, wake after sleep onset, slow-wave sleep, as well as REM sleep. As such, researchers determined that cannabis was useful as a short-term sleep aid, especially in regards to sleep onset.
They also noted its long term adverse effects such as habitutation (the need to use more and more cannabis to obtain the desired sleep-promoting effects) and sleep disturbances, which are liable to result in user-relapse after quitting.
A more recent body of research originates from the 2000s. These studies have focused more on individual components of cannabis, such as THC and CBD. Thus, they added a number of new variables to the cannabis/sleep equation. The type of constituent, ratio of constituents, timing of administration, dosage, and method of administration have all been determined to play major roles in the resulting effect.
THC and Sleep
The cannabis constituent responsible for decreased sleep onset latency (falling asleep faster) is THC. It has been found that during THC administration, circadian rhythms are less pronounced.
The chronic administration of the compound leads to the development of tolerance however. Following discontinuation of THC administration, sleep disturbance (a classic cannabis withdrawal symptom) may occur, lasting as long as 45 days in some cases.
The euphoria-related effects of THC are obviously also undesirable when associated with therapeutic use.
CBD and Sleep
CBD counters some of THC’s undesired effects and it does not seem to elicit dubious effects of its own.
Still, the way it works on sleep is peculiar to say the least. Depending on the dosage, it can have radically opposite effects.
At low doses, it actually induces alertness in the user. At higher doses (around 160 mg per day), it acts as a sedative, improving the quantity and quality of sleep.
At that exact dose, it has been found that CBD increased sleep time, while reducing the number of arousals in insomnia sufferers. Given the overall positive feature-profile of the compound, that makes it the prime candidate for therapeutic use, out of all cannabis constituents.
While the findings were certainly promising, they do have to be taken with a grain of salt still. What we can certainly say is however that they definitely warrant new research in this direction.
Using the whole cannabis plant for improving sleep quality is still relatively common among medical users. The recommendation in such cases would be to go for high CBD content solutions.
Cannabinoids vs Other Sleep Disorders
Cannabinoids and Insomnia
Given the effects of the two constituents (CBD and THC), the former has been deemed more fit to address the issue of insomnia. Defined as an overall dissatisfaction with the quality and quantity of sleep one gets, as well as difficulty falling asleep, insomnia is an ailment affecting almost 20% of the adult population of the US.
In animal studies, CBD was found to increase total sleep time. Interestingly, the effects of CBD were dose dependant. The best results were obtained with mid-range as well as high-dose CBD injections. Low-dose CBD actually worsened sleep onset latency, exerting a stimulating effect.
Another peculiarity was that high-dose CBD increased sleep latency on the day of the administration. Mid-range dose CBD, on the other hand, decreased REM sleep latency the day after administration.
The conclusion of the mentioned studies was that CBD likely exerted its sleep quality-improving effects through an anxiolytic pathway. That would also explain the findings linked to CBD and PTSD, detailed below.
In further studies on humans, CBD was combined with THC. According to the results of these studies, the combined compounds decreased stage 3 sleep.
While initially, THC promoted lower sleep latency (falling asleep quicker), over time, this effect dampened, suggesting the development of a certain degree of tolerance.
Cannabinoids and OSA (Obstructive Sleep Apnea)
Avery dangerous sleep disorder, often associated with cardiovascular problems, OSA plagues some 9% of all American adults. OSA is generally treated with CPAP machines – devices that keep the airways from collapsing, through continuous positive airway pressure. Such devices are cumbersome however and the discomfort they generate often renders them useless for most OSA sufferers.
Research based on animal models suggests that cannabinoids may provide a much more workable solution for the problem. One study aimed to uncover the effects of the endocannabionid oleamide and the exo-cannabionid THC on apneic events.
Its results were unsurprising: both compounds reduced the frequency of apneic events. Researchers drew the conclusion that the endocannabionid system can effectively suppress OSA symptoms that are serotonin-mediated.
A subsequent study used the synthetic THC extract dronabinol, injecting it directly into the nodose ganglion of rats. Its findings confirmed those of the above mentioned study: dronabinol effectively suppressed serotonin-mediated OSA symptoms as well.
Further dronabinol studies have found that the benefic OSA-related effects of the compound were exerted through both CB1 and CB2 receptors. Yet another study found no significant reduction of OSA symptoms in rats treated with intracerebroventricular dronabinol injections. The conclusion was that dronabinol acted against OSA through the peripheral rather than the central nervous system.
Studies were later extended to humans. Once again, the anti-OSA effects of endocannabinoids such as OEA and AEA were confirmed. Dronabinol doses of 2.5-10 mg per day were also found to elicit significant OSA event frequency-reduction. Furthermore, they found the extract safe and well-tolerated.
The bottom line on OSA is that synthetic cannabinoid extracts positively impact its symptoms, over the short-term at least. To confirm this effect over the long run, further studies are needed.
Cannabinoids and REM Behavior Disorder
This is one area of parasomnias which has hardly been investigated thus far in conjunction with cannabinoids. Still, the results yielded by a single study are promising. CBD has been found to positively impact the symptoms of RBD.
Four adults with Parkinson’s disease took part in the study and they all ended up reporting a significant reduction of their RBD symptoms after administration of CBD.
The small sample-size does not lend much credibility to the mentioned results however. At the very least, this same study should be repeated, using a much larger sample-size.
Cannabinoids and Nightmares
The cannabinoids-nightmares link was first explored in the context of PTSD. Persistent nightmares that accompany PTSD are apparently nearly impossible to eliminate or even alleviate. There is just one pharmacological solution available for it now, not a particularly effective one at that.
War veterans were the first to begin experimenting with cannabis for PTSD-related nightmares. Sparked by the anecdotal evidence resulting from that exercise, some actual research was done on the matter.
Researchers used nabilone, another synthetic version of THC, to determine whether cannabinoids could reduce the frequency and severity of PTSD nightmares. The results were encouraging.
In both military service members and prison inmates, nabilone reduced the presence as well as the intensity of nightmares. In addition to that, it also improved the quality and quantity of sleep.
While the results were hailed as a success, they came accompanied by a number of undesired side effects, such as dizziness, dry mouth, and headaches.
Cannabinoids and Daytime Sleepiness
Daytime sleepiness may not seem like a big deal at first glance, but its adverse effects on overall quality of life are significant.
People struggling with this condition get the urge to fall asleep during the day. Such sleepiness may be triggered by medication, by various medical conditions and psychiatric problems.
Sleep disorders such as OSA and narcolepsy may also be involved.
The limited studies done on cannabinoids and Excessive Daytime Sleepiness (EDS) have yielded very peculiar results.
It has been proven for instance, that individuals with THC in their system (due to recent cannabis use) were much more likely to be affected by EDS. They also presented higher risk for narcolepsy.
Surprisingly, CBD was found to have a positive impact on the management of somnolence. It actually countered the sedative effects elicited by THC. Apparently, during the daytime, the two cannabinoids work in a manner which is the exact opposite of their nighttime effects.
Cannabinoids and Chronic Pain
Chronic pain is a major issue affecting a surprisingly large segment of the population. Around 20% of adults live (and sleep) with chronic pain, and the numbers are expected to get worse.
Obviously, chronic pain and quality sleep do not mix. Researchers have only recently sunk their fangs into the impact of cannabinoids on sleep and chronic pain. As such, there isn’t a solid body of research available on the issue yet. Most of what’s been done has been focused on Sativex, a 1:1 THC/CBD concoction, which yielded more than promising results.
The clinical trials featured a self reporting-based methodology, so their findings cannot be considered iron-clad. Most of the participants in the mentioned study reported improvements in sleep quality.
According to other similar studies however, Sativex did not increase objectively measurable sleep duration, despite the self-reported improvements in overall sleep quality.
Another synthetic cannabinoid trialed for chronic pain was nabilone. The effects of nabilone were compared to those of amitriptyline.
Interestingly, both compounds yielded improvements in sleep quality, but nabilone’s impact in this regard was more significant than that of amitriptyline.
Cannabinoids and Anxiety
Although anxiety is often an accompanying ailment of PTSD, it is not limited to PTSD sufferers. Childhood anxiety is for instance a real problem. Believe it or not, cannabionids have been considered for this problem as well.
Anxiety elicits its sleep-disturbing effects by affecting the REM stage of sleep. In fact, it suppresses REM sleep, thus depriving the sufferer of what’s possibly the most essential stage of a good night’s sleep.
CBD was shown to have positive effects on anxiety-induced REM sleep suppression. In fact, it quite successfully blocked this suppressive effect. It accomplished this without affecting NREM sleep in any shape or form.
Early research focused on plant cannabis yielded mixed results regarding the impact of the active compounds on sleep. Later, the confusing nature of these findings was explained away through the different effects that various cannabis constituents exerted in this sense.
According to our current understanding, THC may offer some short-term benefits regarding sleep. More precisely, it helps with sleep onset. Over time however, its benefic effects fade away. Its undesirable side effects on the other hand jump to the forefront. It suppresses the circadian cycles to a certain degree (makes them less pronounced). It ends up promoting daytime sleepiness, memory issues and negative mood.
Its synthetic extracts, dronabinol and nabilone seem to work well for OSA and nightmares though.
CBD is the more promising constituent. It is non-intoxicating, hardly addictive and it impacts sleep quality. In low doses, it is stimulating. In high doses, it acts as a sedative.
While by itself, high dose CBD improves sleep quality and quantity, effectively combating insomnia and a number of other sleep disorders, when combined with THC, it acts to the detriment of stage 3 sleep.
Interestingly, this sort of combination (Sativex) has been proven to improve sleep for chronic pain sufferers.
The bottom line on these studies and on the science thus far is that they warrant a further scientific push in this direction. The link that exists between the endocannabinoid system and the circadian regulation system makes it clear that this is indeed the right path to address and to eventually heal a high number of sleep disturbances.
Future research will have to focus on factors such as: dosage, timing of administration, route of administration, and constituent ratios. The key to better sleep may well be hidden in these details.