Cannabis use in IBS patients is on the rise.
Being that we’re in Canada, cannabis is easy to access now that it’s legal, often leading to self-medication.
But what does the evidence say about cannabis for irritable bowel syndrome, specifically? Today we will be talking about the use of cannabis in medical therapy for IBS. I am by NO means an expert in cannabis, but with so many patients asking about cannabis use for IBS, I have reviewed the literature, and attended a variety of different educational events on the appropriate use of cannabis to provide this informational blog post on if cannabis is appropriate for IBS patients.
What is Cannabis?
Cannabis is a type of plant that produces a chemical called phytocannabinoids that can be smoked, vaped, or orally consumed. The two major phytocannabinoids you hear about that naturally occur in a cannabis plant are D9-tetrahydrocannabinol (THC) and cannabidiol (CBD), however there are 100’s of chemicals, including terpenes, flavonoids, and other phytocannabinoids. These phytocannabinoids interact with our ‘endocannabinoid system’, producing a variety of different effects in the body.
THC is the compound responsible for the psychoactive effects of cannabis that produces a high or euphoria. CBD also has psychoactive effects but will not produce a high or euphoria.
How is Cannabis Taken?
Smoking – is not recommended as burning cannabis releases toxic chemicals. It is important to understand that smoking cannabis is just as dangerous as smoking cigarettes.
Vaping – reduces likelihood of inhaling toxic chemicals and has less impact on the respiratory system. Fast acting, but effects fade after a few hours (5-30 minutes and can last 2-4 hours)
Oral – Slow acting, but effects last longer (60-90 minutes and can last 6-8 hours)
Our Endocannabinoid System
Our body has its own system to produce and manage ‘endocannabinoids’ – or cannabinoids that are produced in the body. We’re still learning a lot about the endocannabinoid system, however, it’s proper function, or ‘tone’ is necessary for almost all aspects of our health and wellness, including:
- Immune function
- Appetite & digestion
- …. And so much more
Since the discovery of the endocannabinoid system, researchers and medical professionals have been hypothesizing how we can use ‘exogenous cannabinoids’ (synthetic & phyto – or plant-based cannabinoids produced outside the body) to regulate the endocannabinoid system and provide therapeutic treatments for a variety of different conditions.
While the research is exciting, it’s crucial that we understand the risks, benefits, and limitations of using cannabis.
At this point, there are a lot of biases we need to be aware of in the research – that limits the potential quality of the studies. Not only that, but as always, citing animal research to provide human recommendations is never appropriate, yet it’s what I see a LOT of people doing online! As a dietitian, my biggest concern with cannabis use is the self-medication, without fully understanding the risks.
What are the risks of using cannabis?
Cannabis isn’t without risk – and with the legalization of cannabis, I see people dismiss the risks associated with use. It’s crucial that we understand cannabis isn’t risk free just because it’s legal, and it’s why I encourage patients who are interested in using cannabis for therapeutic purposes to pursue the medical route rather than self-medicate. A prescribing physician will review your individual risks based on your medical history so that you can make an informed decision and choose appropriate forms & strains of cannabis.
Some risks of cannabis include:
- Increased risks of motor vehicle accidents (remember – CBD still has psychoactive effects without it intoxicating you!)
- Nausea or vomiting (with THC or excessive oral intake)
- Liver disease and fibrosis (especially those with pre-existing liver conditions)
- Increased risk of cardiac disease
- Cognitive impairment with acute or excessive use
- Increased risk of bronchitis (for smoking/vaping)
- Psychosis (especially in high THC users)
- Increase in social anxiety for chronic users
- Risks in those with a history of mental health issues
- Violent behaviour (synthetic cannabinoids)
- Suicidal ideation (synthetic cannabinoids)
- Cannabinoid hyper-emesis syndrome (chronic excessive use)
- Depression/Anxiety (chronic excessive use)
- Addiction / Cannabis use disorder
- Cannabis withdrawal
Endocannabinoid System and IBS
The endocannabinoid system is present in the GI tract, and is mostly localized to the enteric nervous system. Receptors for cannabinoids are also present on epithelial cells (our gut wall) – making the endocannabinoid system in the gut a potential target for diarrhea, pain, nausea & vomiting, and gut inflammation.
It appears that in IBS, endocannabinoid signaling is altered compared to normal population. Not only that, but some research suggests that those with IBS may also have difficulties naturally producing their endocannabinoids – something being termed ‘endocannabinoid deficiency syndrome’. Since cannabinoids can affect gut motility (movement) and visceral sensation (pain & nausea) it’s been postulated that administration of synthetic or phytocannabinoids may help with pain and symptoms of irritable bowel syndrome. But what does the research say?
So far, almost all studies done in IBS have primarily been with synthetic cannabinoids, specifically dronabinol. One study had been completed with THC specifically. The study results are very mixed, with one study showing a slight benefit on reducing IBS-D symptoms, but the remaining studies showing no benefit specifically on visceral hypersensitivity, or pain. Interestingly, participants in one study with a genetic polymorphism in genes dictated possible response, underscoring that cannabis may only have benefit for IBS in certain genetic variants.
The majority of research looking at the mechanisms of action of the endocannabinoid system in the gut are in animal models, and while exciting – it’s important to understand that this may not represent a human endocannabinoid system and its functioning.
At this point, the research does NOT suggest that synthetic cannabis or THC will help with IBS symptoms.
More research is being done on CBD as well as other phytocannabinoids to look specifically at chronic pain and inflammation, which may in turn influence IBS symptoms.
Where patients may see benefits of cannabis
IBS is a condition where patients struggle with abdominal pain and often have concurrent anxiety. So, it’s no surprise that some patients anecdotally report cannabis, especially CBD to helping to reduce pain and anxiety. However, I do have to say that many patients I see also have had negative experiences using cannabis.
From a research perspective, most studies have been done in rats up to this point, making it hard to provide recommendation around appropriate cannabis use. There is weak supportive evidence for the use of certain cannabinoids in neuropathic and inflammatory pain, which can be concurrent to IBS symptoms. There is also weak evidence to support cannabis’s impact on sleep and anxiety which in turn, may reduce IBS symptoms.
At this time, we cannot recommend cannabis for irritable bowel syndrome, however with the favourable safety profiles of CBD specifically, and the up and coming research, it may be worth discussing appropriate use with your gastroenterologist if all other treatment modalities have been insufficient.
Improving your Endocannabinoid Function – without Cannabis
Our endocannabinoid system plays a major role in how we function. It’s no surprise that certain self-care and wellness activities have a positive impact on the endocannabinoid system. In fact, there are many things you can do without cannabis that may improve your endocannabinoid tone (and, help with IBS symptoms!).
- Reducing stress (our digestive health psychologist can help!)
Diet and the Endocannabinoid System
Many dietary components have been found to activate and regulate endocannabinoid system tone. While more research is required, these are simple, food first strategies that pose additional benefits and are worth adding into your diet!
Increasing intake of terpenes & flavonoids
These compounds have been shown in animal models to activate cannabinoid receptors. Terpenes are aromatic compounds that have medicinal effects. Diets high in terpenes optimize endocannabinoid function.
Bottom line: eat a variety of plant-based foods with lots of flavour! Compounds found in some of our favorite herbs, such as thyme, bay leaves, lemon grass, pepper, cloves, basil, peppermint, and citrus may have positive effects on the endocannabinoid system.
Increase intake of polyunsaturated fats
Diets high in polyunsaturated fats are required for the synthesis of endocannabinoids in our bodies. Include a variety of fatty fish and plant-based fats such as olive oil, avocado, sesame oil, whole grains, flax, nuts, and seeds to increase your intake of these fats.
Key Take-Aways for Cannabis in IBS
- The evidence is very weak at this point to recommend cannabis for IBS
- Further research is required looking at different components of cannabis, specifically CBD
- Always discuss your personal risks of using cannabis, as it can vary based on your past medical history. Cannabis is contraindicated in certain cases.
- If you are taking cannabis for a medical reason, ALWAYS work with a medical prescriber to ensure you start low, go slow and stay low. Never drive on any form of cannabis.