How Cannabis Can Treat Inflammation

Overview

There is scientific evidence suggesting that cannabis can reduce inflammation and may be able to help treat conditions that are either caused by inflammation or have it as a key symptom, such as rheumatoid arthritis, multiple sclerosis, inflammatory bowel disease, and hepatitis. Still, some research suggests cannabis can also increase inflammation in certain circumstances. 

The body’s endocannabinoid system plays a role in regulating inflammation responses — which is how cannabis is able to have inflammation modulating effects. Unfortunately, current research is lacking information on how to best utilize cannabis as a treatment for inflammation.

Research on inflammation and cannabis

Cannabis has been used for inflammation throughout the ages. As far back as the 1st century, Roman philosopher and commander Pliny the Elder recommended using cannabis for the inflammatory condition gout. In modern times, we know from animal studies that cannabis has strong anti-inflammatory properties, and many humans use cannabis to relieve symptoms of inflammatory conditions like rheumatoid arthritis, multiple sclerosis, inflammatory bowel disease, and hepatitis.

In experimental models of rheumatoid arthritis (RA), cannabis’ anti-inflammatory effects have been shown to protect patients from the progression of the disease by reducing inflammation in the body. In one double-blind study on cannabis for RA patients, researchers found that cannabis not only relieved pain for these patients, it could also suppress the inflammatory activity of the disease. 

Studies also show cannabis can help with multiple sclerosis (MS), in part by reducing inflammatory chemicals like cytokines produced in the body. In eight separate clinical studies, MS patients given cannabis reported improvement in symptoms and did better on objective measures like handwriting and bladder control tests. 

Studies on inflammatory bowel diseases (IBD) like Crohn’s disease and colitis, have also shown some potential for treatment with cannabis. Animal studies show that cannabis’ active ingredients are capable of modulating the kind of inflammation in the GI tract that we see in IBD. Survey based studies on IBD have also found that cannabis can relieve its symptoms. Indeed, marijuana is an approved therapy for IBD in most jurisdictions where it is medically legal. 

In human studies, including one placebo-controlled study, researchers have found that cannabis use was associated with improvement of disease activity in Crohn’s disease and reduction of other medications. Unfortunately, one study also found that cannabis use is associated with greater risk of requiring surgery for Crohn’s disease — which complicates our understanding of cannabis’ impact on this condition. 

Cannabis may also help reduce viral infection related inflammation — in some cases also reducing the overall death rate. In animal studies, cannabis’ active chemical THC was able to protect mice from hepatitis, by reducing inflammatory responses. Some studies also showed it could help reduce risk of sepsis (a dangerous inflammatory response that can occur with infection) and even improved recovery rates for infections like malaria. But importantly, in other animal experiments, cannabis use decreased survival rates for influenza. 

Other studies show cannabis’ inflammatory reductions may help reduce the growth of certain cancers that are triggered by chronic inflammation.

CBD and inflammation

Inflammatory relieving properties have also been found for CBD, a medicinal chemical found in cannabis which doesn’t cause the kind of psychotropic high we see with THC. For example, in animal models of rheumatoid arthritis, CBD stopped the progression of arthritis, while also relieving symptoms like pain. 

There is also animal research suggesting that CBD can reduce inflammation in the gut

Still, in one study, low dose CBD (unlike THC) did not show any impact on the progression or symptoms of Crohn’s disease. 

That said, one review of the literature found that CBD could be a helpful treatment for inflammatory conditions, because it can stop or slow inflammatory factors like the production of cytokines. 

Other studies looking at CBD’s effects on inflammation suggest that it may be particularly helpful for certain cardiovascular disorders, inflammatory bowel diseases, rheumatoid arthritis, types 1 and 2 diabetes, atherosclerosis, Alzheimer disease, hypertension, the metabolic syndrome, ischemia-reperfusion injury, depression, and neuropathic pain.

How cannabis works on inflammation

The endocannabinoid system (ECS) exists in all vertebrates and helps regulate crucial functions such as sleep, pain, and appetite. The human body produces its own cannabinoids, which modulate and activate its various functions, but as its name suggests, the endocannabinoid system can also be modulated and activated by cannabinoids found in the cannabis plant. Because the entire system was only discovered in the past 30 years, scientists still have much to learn about the myriad ways cannabis affects the human body.

When it comes to modulating inflammation, cannabinoids mainly work by stimulating the ECS’ primary receptors, CB1 and CB2, along with lesser known receptors associated with the system. Our bodies’ natural cannabinoids, like anandamide and 2-AG, play an important role in these inflammatory effects, signaling increases and decreases in inflammation via these receptors, but external cannabinoids from cannabis can also stimulate these functions.

When cannabinoids stimulate the ECS receptors, they cause a number of anti-inflammatory effects, such as reducing cytokine and chemokine production (which are markers of inflammation), increasing T-regulatory cell activity (which suppress inflammatory responses). 

Still it’s notable that while cannabinoids can reduce certain inflammatory factors, they can increase others, in some cases worsening inflammation. For example, in one study, levels of an anti-inflammatory cytokine decreased and a pro-inflammatory cytokine increased in response to THC. Some researchers say this suggests different types of cells may respond differently to cannabinoids when it comes to inflammation. 

In addition, some research has indicated cannabinoids may impact inflammation through routes other than receptor stimulation as well. But more research is needed to fully understand these alternative mechanisms.

Using cannabis for inflammation

If you are using cannabis for the treatment of inflammation, the best first step is to talk to a doctor who specializes in cannabinoid medicine. Because inflammation is a symptom present in a variety of conditions that have different factors to consider, the best way to utilize cannabis for inflammation may differ with each condition. Your treatment should be tailored to your specific condition — rather than inflammation in general. 

Still, the research is fairly limited when it comes to specifying how to best utilize cannabis for inflammation with any of these conditions. The research above includes studies using a few different methods for taking cannabis, including inhalation, oral ingestion, and rectal suppositories. Studies also show that cannabis can reduce inflammation when used topically. But there have yet to be comparisons on whether any methods outperform the others in terms of treating inflammation. Similarly, the studies above show cannabis’ main compounds, THC and CBD, are both able to reduce inflammation — separately or in combination with each other — but don’t tell us whether one or the other might be superior in creating these effects.

Potential side effects of cannabis use

Cannabis can also have side effects — particularly high-THC cannabis. These may include temporary psychoactive effects such as mental confusion, lightheadedness, euphoria, anxiety, and slower cognitive skills; or uncomfortable physiological changes like, coughing, allergies, dry mouth and eyes, increased appetite, heart palpitations, and drowsiness. 

For inflammation treatment, it’s also important to note that while cannabis often reduces inflammation, some research has shown its ability to increase inflammation as well. In addition, there is a worry from some researchers that cannabis’ pain relieving properties might mask ongoing inflammation.