[toc] For a long time, marijuana (cannabis, pot, weed, or a thousand other names) has suffered under prohibition in the United States. Although many individual states had already instigated their own legislation, it was the 1937 Marijuana Tax Act that effectively prohibited all use of cannabis on a federal level.
But fast forward to the present, and society’s attitudes toward weed have made some dramatic u-turns.
2012 was the real turning point, when Colorado and Washington became the first ever states to legalize the recreational use of marijuana for adults aged 21 years or older.
Secondly, the decades-long war on drugs has been hailed by experts as a set of “failed policies and failed practices”, tackling neither the issues of drug trafficking nor drug-related violence. Contrast this with Portugal a country that decriminalised all drug use 15 years ago, and has not seen a significant increase in drug use during that time.
There’s also the issue of money. Marijuana is a huge growth industry right now. North American marijuana sales topped $6 billion in 2016 and are forecasted to hit $20 billion by 2021. And money is very good at changing people’s attitudes.
But lastly, and perhaps most importantly, there’s the growing widespread acknowledgement in medical and scientific communities of the huge potential benefits of cannabis derived medical products.
Although cannabis has a number effects on sleep architecture, many studies have shown cannabis to be an effective sleep aid due to its effect on the body’s endocannabinoid system to relieve stress and produce a sedative effect.
The number as well as the availability of cannabis-based medications increases, but are they really as effective as the labels suggest?
Some suggest that cannabis-based medications have several advantages compared with traditional prescription sleeping pills, such as Behadryl, Lunesta, and Ambien, citing cannabis as being less addictive and more effective for long-term use, promoting muscle relaxation, and improving mood.
Early investigations of the effect of cannabis on sleep gained momentum in the 1970s. Even though they produced mixed results, the interpretation of findings was considered unreliable due to small sample sizes.
More recent investigations have provided data on various qualitative and quantitative sleep-related measures. According to them, the current understanding is still clouded by mixed findings. However, there are some important patterns emerging.
Cannabis and sleep stages
Sleep has five stages, and cannabis affects all of them. Specifically, it can change the duration and intensity of these stages.
The First Stage of Sleep
The person finally falls asleep. The stage typically lasts for 7-10 minutes, but could take longer if the person experiences pain and stress. Given that cannabis can relieve both of them by providing the relaxation feeling, its impact on this stage is positive.
The Second Stage of Sleep
The sleep is still light at this stage and the person could wake up very easily. According to the research, cannabis provides the least impact on it.
The Third and Fourth Stages of Sleep
Often, these stages are viewed as a single one. They are the most restorative and cannabis prolongs them. Therefore, it can provide a positive impact here as well.
The Fifth Stage of Sleep
This is the most important stage during which dreaming occurs. The research claims that cannabis use decreases REM sleep, so a frequent marijuana user has a lower occurrence of dreaming. This effect is explained by the fact that cannabis blunts response to dopamine.
What chemicals are involved?
Arguably the most important active ingredient is tetrahydrocannabinol more commonly referred to as THC , whose neural effects are mediated through receptors in the brain. As the result of this process, sedation occurs.
A 2013 Current Addiction Reports article written by a group of researchers from California suggested two primary mechanisms that explain how THC produces sedation. These mechanisms are described in table 1 below.
How does tetrahydrocannabinol (THC) causes sedation?
CB1 receptors are aroused by neurons involved in the lateral hypothalamus, thus inhibiting the arousal system
Cannabinoids like tetrahydrocannabinol are effective in increasing the level of adenosine, which is a chemical that promotes sleep
Tabled adopted from Sleep disturbances: Implications for cannabis use, cannabis use cessation, and cannabis use treatment, published in Current Addiction Reports, 1(2), pp. 109-114.
A complex relationship
However, even though cannabinoids have the potential for promoting sleep, the studies on their effect caused contrasting findings.
For example, studies using high doses of tetrahydrocannabinol tended to produce an activating response in participants, while the ones using low dose reduced sleep latency.
The reason that explains different findings is the nature of tetrahydrocannabinol’s influence. According to scientists, this component produces excitatory effects while the sedating mechanism activates later.
But does the science has the solution for reducing stimulating effects and promoting sleep in those who suffer from sleep disturbances?
Enter cannabidiol otherwise known as CBD. This is another interesting cannabis constituent that has been known to counter stimulating effects of tetrahydrocannabinol. It is the second most active component that is used in a variety of cannabis-based medicines (CBM) designed to treat various health problems, including sleep disorders.
Although the administration of CBMs containing CBD has been shown contrasting effects as well, the dose and the timing of administration were critical factors to increase the effectiveness of treating insomnia and related disturbances.
As we continue to discover more health effects of cannabis, it also studies how its usage relates to sleep outcomes and mental health condition. The body of the current research suggested that motivation to use cannabis for sleep-related issues is high and initially benefits sleep in a significant way but the progress wanes over time.
The frequency of marijuana use was another important factor because it has a profound effect on the sleep quality. For example, one study published in Journal of Addictive Diseases included patients with insomnia who were suffering from depression and those who did not found that daily users had a higher rate of insomnia. On the other hand, non-daily users’ Insomnia Severity Index scores were lower than in daily users and controls.
Insomnia Severity Index in daily users, non-daily users, and non-users controls was 38.8 percent, 10.3 percent, and 20 percent respectively. These results suggested that occasional cannabis use (non-daily) was the most beneficial for battling insomnia.
Cannabis and sleep apnea
Sleep apnea is a dangerous disorder that affects breathing during sleep. The latest statistics suggested that an estimated 18 million Americans are affected, with thousands more undiagnosed. A group of scientists from the University of Illinois at Chicago stated that THC stabilized autonomic output, reduced sleep-disordered breathing associated with sleep apnea, and decreased the severity of the condition.
In their study, seventeen young participants who were given cannabis pills (dronabinol) before bed. All of the demonstrated improvement in sleep patterns, so it was one of the first studies to support safety and tolerability of this drug in patients with obstructive sleep apnea.
The future of cannabis and sleep
Although many studies on the effect of cannabis on sleep were performed, this area is still in its infancy and a lot of reliable, peer-reviewed data is needed to make solid arguments. However, at this point, it is clear that cannabis-based medications have the potential to contribute to the treatment of sleep-related disorders.
This, of course, raises some important questions concerning the future use of cannabis in medicine. Should the medical community be open to the possibility of developing more drugs based on cannabis? Should research on their effect on sleep disorders continue and expand? Given that legal status of marijuana is still a topic of a rigorous debate, many healthcare researchers do not feel comfortable conducting studies related to cannabis.
At this point, the effects of cannabis are still mixed, so the future should yield some more fruitful discoveries.