Studies show that high-dose CBD and low-dose THC help treat sleep disorders.
Increased scientific interest in using cannabis and cannabinoids to help treat sleep disorders has resulted in a recent spike of studies. These investigate the ability of cannabis to help: sleep apnea, insomnia, REM behaviour disorder and nightmares (particularly associated with PTSD).
Studies found that cannabidiol (CBD) and delta-9-tetrahydrocannabinol (THC) may have therapeutic benefits for treatment of insomnia, while others considered synthetic cannabinoids as a treatment for apnea and REM behaviour disorder. What is the potential here?
Recent work demonstrates that the endocannabinoid system regulates circadian rhythm and sleeping. This means irregular sleeping dysregulates the endocannabinoid system.
Improvement of the endocannabinoid signaling (at the receptor level) restores previously abnormal sleep. Studies conducted on humans have reveal that THC and CBD impact sleeping differently. The changes depend on the dose and route of administration. Using one or the other, you can achieve different effects.
Specifically, high-dose CBD and low-dose THC can have therapeutic effects on sleep. For example, in a study among people suffering from insomnia, administration of 160mg/day of CBD resulted in increased total sleep time and decrease nocturnal awakenings, likely indicating a higher depth and thus quality of sleep. On the other hand, low dose CBD administration was found to promote wakefulness in other studies.
Pre-clinical studies corroborated these findings, showing that CBD has beneficial effects on quality of sleep/wake cycles. Furthermore, CBD oil associates with decreased insomnia and PTSD-related disturbances. While some medicinal cannabis users experience earlier onset of sleep, others did not experience this benefit. Altogether, these studies suggest that the mechanism of CBD in improving rest quality and duration is related to its anxiolytic (anti-anxiety) effects, while the effects of THC vary depending on its concentration and route of administration.
Obstructive sleep apnea (OSA) is the most prevalent form of disordered breathing affecting approximately 10% of the adult population in North America. It is characterized by at least 15 episodes of cessation of breathing per hour (apneic events) while sleeping due to the collapse of the upper airway. This, of course, is detrimental to the oxygenation state of all organ systems, and results in a myriad of symptoms such as daytime sleepiness, irritability, inability to focus etc.
Recently, pre-clinical studies found that both endogenous (oleamide) and exogenous cannabinoids (THC and synthetic THC dronabinol) reduced the number of apneic events. These studies found that the reduction of apneic events associates with serotonin-induced modulation of upper airway muscles. This indicates that the cannabinoid signaling interacts with serotonergic signaling, making the upper airway more rigid and less likely to collapse, preventing the apnea from occurring.
CB Receptors and Sleep
Further work has demonstrated that this effect is conveyed via both CB1 and CB2 receptors, suggesting the potential for THC modulation of both receptors. Synthetic THC dronabinol was used in a preliminary study in humans with OSA, and the authors found that it was safe, well tolerated and efficacious in reducing apneas when administered in doses from 2.5 mg-10 mg daily. Taken together, THC and THC synthetic cannabinoids seem to be beneficial in treatment of OSA. Both human and animal studies prove this. They find that the mechanism of action includes modulation of serotonin signaling to prevent the collapse of the upper airway.
Promising cannabinoid use data relates to other sleep-related ailments. These include REM behaviour disorder, insomnia, daytime sleepiness and sleep in pain conditions. Doctors found CBD suppresses REM behaviour disorder. Study participants tolerated the CBD well. CBD and THC administered in a 1:1 ratio mitigated daytime sleepiness. The same mixture of cannabinoids in form of Sativex resulted in improvement in sleep quality among chromic pain patients.
We have limited research so far on cannabinoids and sleep. Nevertheless, the connection between the endocannabinoid system and circadian rhythm provides a theoretical link between cannabinoids, sleep, and disordered breathing.
The Best Strategy?
The work so far reveals that the medium to high doses of CBD may be the winning strategy. These doses improve sleep. A mixture of 1:1 of CBD and THC may aid patients with chronic pain. People are producing new formulations of products containing different doses of cannabinoids. We’re always discovering new cannabinoids. Slowly but surely, our gaps in knowledge are filling. Soon, we’ll reveal the full potential of cannabinoids’ therapeutic benefits.