Cannabis and COVID-19: What the Research Says About Immune Health
Cannabis Calms Immunity, But Some Should Stay Away
The intersection of cannabis and COVID-19 has led to some fascinating discoveries, with a recent study showing that cannabis users had MUCH better outcomes compared to non-users when battling severe COVID-19. But as with any promising headline, there’s more to the story. Let’s break down the facts, the takeaways, and what this means for patients and healthcare professionals navigating the complexities of COVID-19 and immune health.
For those who like to read the full study, here it is
Here’s the news report in Forbes
What the Study Found
The study compared outcomes for cannabis users and non-users hospitalized with COVID-19. The results showed that cannabis users had significantly lower rates of serious complications:
Severe COVID-19 infection: 46.6% in non-users vs. 28.2% in cannabis users.
Intubation rates: 9.7% in non-users vs. 7.1% in cannabis users.
Mortality: 5.1% in non-users vs. 2.8% in cannabis users.
Hospital stay: Cannabis users stayed in the hospital slightly less (7.0 days for non-users vs. 6.4 days for cannabis users).
These numbers suggest that cannabis seems to play a big role in helping patients avoid some of the worst complications of COVID-19, including the need for mechanical ventilation and, ultimately, death.
Why Cannabis Could Make a Difference
One of the key reasons cannabis might lead to better outcomes rests in its ability to calm an overactive immune system. In severe COVID-19 cases, the immune system can go into overdrive, causing what’s known as a “cytokine storm.” This uncontrolled inflammation leads to many of the serious complications of COVID-19, including lung damage, respiratory failure, and multiorgan failure. Yeah, it’s awful. Reports from pathologists doing autopsies in the early days of COVID-19 were shocking - evidence of the immune system wreaking havoc on its own body, trying to kill the virus that was invading everywhere.
Cannabis, particularly the cannabinoids, terpenes, and even some flavonoids, have been shown to have strong anti-inflammatory effects. In some cases, 30-50 times stronger than steroids! By calming the immune response, cannabis seems to help prevent this dangerous overreaction, potentially saving lives in the process. It’s an idea that’s compelling, and it certainly matches what we’re learning at CED Clinic, from patients suffering acute infections, and equally helpful for symptoms of Long-COVID. As we continue to see long-term effects in many COVID-19 survivors, and (sorry) as more pandemics come to mix with our ever-globalized society, this could be a spectacular opportunity for public health benefit.
What the Study Didn’t Show
While the results are promising, the study has important limitations. First, it didn’t look at how cannabis was used—whether people were smoking it, consuming edibles, or using oils. Different forms of cannabis can have different effects on the body, so the lack of clarity here leaves some open questions. Additionally, the study didn’t track how MUCH cannabis people were using, which could also play a significant role in the outcomes.
Another issue is that the study relied on medical coding data, which can sometimes (perhaps all the time?) be inaccurate. Medical codes don’t always capture the full picture of a patient’s health or their treatments, and sometimes stick around for too long because doctors don’t get rid of old codes, so this could affect the accuracy of the results.
Finally, and most importantly, this was a retrospective study—meaning it looked back at past data. This kind of study can show patterns and associations, but it can’t definitively prove that cannabis caused the better outcomes. Other factors might have played a role in why cannabis users fared better, and without prospective trials (where researchers track patients in real time), we can’t be sure of the direct impact of cannabis on COVID-19 outcomes. Maybe it was the fact that cannabis consumers slept better, had less stress, more laughter, took time out of stressful days… lots of possible confounding factors.
What We Know About Cannabis and the Immune System
The study suggested that cannabis might reduce inflammation through its effects on certain immune receptors (CB1 and CB2 receptors). However, most current research points to cannabis’s direct impact on the CB2 receptor specifically, and the broader inflammatory system (called the cytokine immunity) as the key reason it helps reduce inflammation, not specifically interacting with the CB1 receptors. By reducing inflammation, in general, cannabis might prevent some of the severe complications seen in COVID-19 patients, especially those linked to an overactive immune response.
Also, equally important, there is no discussion of the impact that cannabis has on many other elements of COVID infections. We know that cannabis partially blocks the ability of COVID to enter and multiply within new cells, cannabis can interfere with genetic replication of COVID virii, and more. I did a few talks on the topic back a few years ago, if anyone wants to learn more (see links at the bottom of this post).
While the study doesn’t provide all the answers, it adds to a growing body of evidence that cannabis can help modulate the immune system. In my practice, I’ve seen firsthand the benefits of cannabis in helping patients with overactive immune responses, whether from infections, chronic conditions, or autoimmune diseases. It’s clear that cannabis can be a powerful tool in managing inflammation, but we still need more data to fully understand its potential in COVID-19 treatment.
Video 2 (longer review of Cannabis + COVID)
Video 3 (longer lecture, a review of the literature)
Limitations and What It Means for Patients
The biggest takeaway from this study is that while cannabis shows potential in helping patients with severe COVID-19, it’s not a cure. The study’s limitations—such as the lack of lab data on inflammation levels and the reliance on retrospective data—mean that we can’t definitively say cannabis is the reason for the better outcomes.
It’s also important to note that cannabis isn’t always the right choice for everyone. For example, using cannabis right after a vaccine or for people with compromised immune systems might actually be counterproductive, as cannabis can dampen the immune system’s response. This doesn’t mean cannabis isn’t a useful tool, but it underscores the importance of understanding how it works in different contexts.
Cannabis as Medicine: Proceed with Care
The real lesson here is that cannabis is a serious medicine with serious effects on the body. For some people—especially those with overactive immune systems—cannabis’s ability to calm inflammation can be life-saving. But for others, the same immune-suppressing effects could pose risks, particularly in situations where the immune system needs to be fully active.
Patients should always approach cannabis with care and seek guidance from knowledgeable healthcare providers. Unfortunately, not all doctors are well-versed in cannabis therapy, but there are specialists out there who can help patients navigate their options safely and effectively.
Take These Thoughts With You!
Cannabis continues to show promise as an anti-inflammatory medicine, and this study adds to the growing evidence that it might play a role in managing COVID-19’s immune complications. However, it’s important to remember that cannabis isn’t a miracle cure—it’s a complex medicine that needs to be used thoughtfully and under proper guidance. As research continues, we hope to learn more about how cannabis can help us tackle not just COVID-19, but the many other conditions linked to an overactive immune system.
What Didn’t Make it Into Forbes:
What Didn’t Make It into the Publication: Behind the Scenes of Cannabis and COVID-19
While the article covering the study on cannabis and COVID-19 outcomes is thorough and covers the topic very well, there are several important nuances and insights that didn’t make it into the final print, but had come up in the discussion between me and the author. Here’s a share (behind the scenes look!) at the key points that I think also deserve attention:
1. The Role of Cannabis in Immune Modulation
The article briefly touches on cannabis’s ability to calm an overactive immune system, but the underlying mechanism deserves more emphasis. As I introduced above, the study suggests that cannabis may influence the immune response through CB1 and CB2 receptors. However, emerging research points to cannabis’s broader anti-inflammatory effects that go beyond these receptors. Cannabinoids like CBD and THC have been shown to impact directly both CB2 receptors and the cytokine inflammation pathways, which could explain the reduced severity of COVID-19 complications in users. This broad-spectrum anti-inflammatory action is more central to cannabis’s therapeutic potential than receptor-specific effects alone.
2. The Importance of Inflammation Markers
One of the biggest gaps in the study is the lack of direct data on inflammation levels in patients. Inflammatory markers such as C-reactive protein or cytokine levels would provide crucial insights into how cannabis is influencing the immune system during COVID-19 infections. Without this data, it’s harder to conclusively link cannabis use to reduced inflammation and better outcomes. This missing piece leaves room for speculation and limits the strength of the study’s conclusions.
3. Variability in Cannabis Consumption
Again - this didn’t make it into the article, but the study didn’t account for the type or method of cannabis consumption—whether patients were smoking, using edibles, or vaping. Each method of consumption can have different effects on the body, particularly when it comes to respiratory health. Smoking, for instance, introduces combusted materials into the lungs, which could theoretically worsen respiratory symptoms, while edibles or oils might have a less direct impact. Without this distinction, the study leaves out important context that could change how we interpret the results.
4. Challenges in Data Accuracy
The reliance on ICD-10 codes to identify cannabis use presents another limitation. Medical coding can be prone to errors, and the accuracy of these codes can affect the study’s findings. If cannabis use was misclassified or overlooked in some cases, it could skew the results. This challenge, coupled with the study’s retrospective design, means we must be cautious about drawing firm conclusions from the data.
5. Retrospective Studies and Causality
The study looks back at hospital data, which means it can only show associations, not direct cause and effect. While the results suggest that cannabis users fared better in terms of severe COVID-19 outcomes, it’s important to remember that retrospective studies are limited in their ability to establish causality. Other factors—like underlying health conditions, lifestyle differences, or even access to healthcare—might have influenced the outcomes.
6. The Broader Context of Cannabis and COVID-19
While the study highlights promising outcomes for cannabis users, it’s part of a growing but still young field of research. Other studies have shown varying results, including some that suggest cannabis use might increase the risk of severe COVID-19. The broader picture is still developing, and it’s clear that more controlled, prospective studies are needed to better understand how cannabis influences COVID-19 outcomes.
7. Cannabis Isn’t a Cure-All
It’s important to note what the study doesn’t show: cannabis is not a cure or a preventive measure for COVID-19. There’s no evidence that simply using cannabis will stop you from getting COVID, and the study doesn’t suggest that it should be used as a standalone treatment. As with any medicine, cannabis should be used thoughtfully, under the guidance of knowledgeable healthcare professionals, especially in the context of COVID-19.
Conclusion:
The published study on cannabis and COVID-19 outcomes provides promising data that cannabis may play a role in reducing the severity of infections. However, there are still significant gaps in the research that limit our ability to draw definitive conclusions. Missing data on inflammation levels, variability in cannabis consumption methods, and the inherent limitations of retrospective studies mean there’s more to explore before we fully understand cannabis’s role in COVID-19 treatment. While cannabis may help calm an overactive immune response in severe cases, it’s not a cure and should be used with care. The conversation on cannabis and COVID-19 is just beginning, and more research will be crucial in uncovering the true potential of this plant-based medicine.
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