Here’s the case of a real patient (with a made-up name).
Joe Smith is a 64-year-old cisgender male with a 10-year history of chronic low back pain (CLBP). Over the years, he’s received medical care for LBP including 2 surgeries, and medications “for the pain” including anti-inflammatories, muscle relaxants, and analgesics (aka pain killers), and has also been prescribed anti-depressants and sleep aids. Joe has used the medications as prescribed but hasn’t achieved enough pain relief to tolerate their negative side effects. He has an opioid prescription which he takes “on really bad days” but won’t use the medication more than twice a week because he knows it’s not curing the problem and he doesn’t want to get addicted. He tries to stay active by walking and despite having a desk job doing animation work, he can get up from his desk and move or walk several times a day.
Yes, there are many options that can be made available to Joe to help him manage CLBP. However, right now, he’s asked you, one of his healthcare providers about CANNABIS.
Do you have a ready answer?? If not, read on!
The first thing to consider is whether cannabis is legal in Joe’s jurisdiction. Given the expansion of medical marijuana and adult-use laws across the US, let’s assume that where he lives, Joe can access cannabis legally.
However, as clinicians wanting to practice in a safe and efficacious way, we are challenged by the fact that federally, cannabis is illegal AND has been categorized as a Schedule 1 drug since 1970. This means that the government views cannabis as a drug that 1) has no medical benefit, 2) is highly addictive, and 3) is a potential gateway drug. For over half a century this ill-informed categorization has severely limited research on the true effects and potential of this ancient plant. This has led to wild claims of both the risks and benefits of cannabis. It’s often difficult to separate the science from the hype.
To begin to understand cannabis’ potential for modifying pain let’s start with some basic science. The cannabis plant contains a variety of substances, but that’s beyond the scope of this blog. For now, let’s just focus on 2 of cannabis’ many cannabinoids, delta-9-tetrahydrocannabinol (THC) and cannabidiol (CBD). Both THC and CBD interact with the body’s cannabinoid receptors. You may be thinking what?! There are cannabis receptors in the body?! And the answer is, yes!! (Maybe that helps explain why cannabis had been used medicinally from as early as 2800 BC through the early 1930s to treat a full range of medical conditions, including pain).
Cannabinoid receptors are found throughout the body and are part of the endocannabinoid system (ECS), which was identified in the 1990s. Although scientists still don’t fully understand the ECS, current research suggests that it turns on when the body needs assistance to maintain optimal conditions for proper functions and can help regulate pain sensation, sleep, inflammation, mood, digestion, and more.
Putting this all together, we have a plant (cannabis) that possesses substances (THC and CBD) for which we have receptors in our body, found in a system (the ECS) that plays a role in managing important bodily functions. In cellular experiments and animal studies, scientists have been able to prove that the endocannabinoid system is intimately involved in pain regulation and that THC and CBD play an important role in being able to turn on or turn off receptors associated with pain and its perception. (1)
But what do we know about cannabis and its effect on people who have chronic pain back, and in Joe’s case, for someone who has an opioid prescription but would prefer not to use it?
It’s difficult to find a lot of information because cannabis research has been very restricted for so long. However, in a 2020 retrospective study, researchers found that of 61 people between 49-86 years old who had CLBP for an average of 11 years, 51% had enough pain relief from cannabis that they were able to stop taking opioids completely. (2) In another study of 257 people with CLBP (average age = 61 years), researchers found that cannabis helped to significantly reduce pain and improve quality of life. Plus, over the 1-year study period, 73% of the people were able to either decrease or completely stop their cannabis consumption. (3) Interestingly, over 50% of the study participants did not experience intoxication as a side effect of the cannabis therapy and in a systematic review of the efficacy of cannabis in reducing back pain, there were no serious adverse effects reported. (4)
So, what might you tell Joe??
Let’s turn to an evidence-based medicine (EBM) perspective in which we acknowledge patient values, the best research evidence, and clinical expertise. In Joe’s case, he’s asked you about cannabis, so he’s likely willing to use cannabis as a way of managing his pain. The best available research evidence is lean, but it suggests that cannabis is a viable option to manage CLBP for many people who are similar to Joe. The final piece of EBM is “clinical expertise” which takes into account one’s experiences as a healthcare provider and knowledge about Joe’s medical history and lifestyle.
To do that consider the following: 1) Does Joe have a personal or strong family history of psychosis, mood, or anxiety disorder? 2) Does he have a history of substance misuse disorder? 3) Does Joe have a cardiovascular or respiratory disease? 3) Is Joe’s employment considered to be a safety-sensitive workplace?
If the answer to these 3 questions is “no”, then a reasonable response to Joe would be that based on a few studies, cannabis might help him manage his low back pain.
But now, we’re faced with another challenge…what type of cannabis and delivery method (smoke, edibles, tinctures, etc.) and what dose might help Joe the most.
Stay tuned...another blog post is coming soon.
Citations
(1) Manzanares J, Julian M, Carrascosa A. Role of the cannabinoid system in pain control and therapeutic implications for the management of acute and chronic pain episodes. Curr Neuropharmacol. 2006 Jul;4(3):239-57. doi: 10.2174/157015906778019527. PMID: 18615144; PMCID: PMC2430692.
(2) Takakuwa KM, Hergenrather JY, Shofer FS, Schears RM. The Impact of Medical Cannabis on Intermittent and Chronic Opioid Users with Back Pain: How Cannabis Diminished Prescription Opioid Usage. Cannabis Cannabinoid Res. 2020 Sep 2;5(3):263-270. doi: 10.1089/can.2019.0039. PMID: 32923663; PMCID: PMC7480723.
(3) Greis A, Larsen E, Liu C, Renslo B, Radakrishnan A, Wilson-Poe AR. Perceived Efficacy, Reduced Prescription Drug Use, and Minimal Side Effects of Cannabis in Patients with Chronic Orthopedic Pain. Cannabis Cannabinoid Res. 2022 Dec;7(6):865-875. doi: 10.1089/can.2021.0088. Epub 2021 Nov 12. PMID: 34767730; PMCID: PMC9784606.
(4) Price, R. L., Charlot, K. V., Frieler, S., Dettori, J. R., Oskouian, R., & Chapman, J. R. (2022). The Efficacy of Cannabis in Reducing Back Pain: A Systematic Review. Global spine journal, 12(2), 343–352. https://doi.org/10.1177/21925682211065411