IBS and CBD: Everything You Need To Know

IBS Overview 

Irritable bowel syndrome (IBS) is classed as a functional gastrointestinal (GI) disorder, and is a condition that is not well understood by Conventional Medicine. Diagnostic tests available within the NHS fail to pick up on any clinical abnormalities, and patients usually do not demonstrate any outwardly noticeable symptoms that would suggest anything is wrong with them. 

However, every person with IBS will tell you that they have various symptoms along the lines of digestive distress, abnormal bowel function and often symptoms related to mental health. 

In contrast to Conventional Medicine, Functional Medicine is able to identify key imbalances in various bodily systems, most notably the digestive system, endocrine (hormones), nervous and immune systems which are indicative of IBS. 

IBS can be further sub categorised into constipation-predominant IBS (IBS-C) and diarrhea-predominant IBS (IBS-D). Conventional approaches towards IBS simply focus on the management of the condition, with a focus on alleviating the symptoms. 

Management is tailored to the specific IBS subtype, but would generally include dietary restriction of certain food groups (FODMAP diet) and/or trigger foods, antidepressant medications, antibiotics, and medications that either increase or decrease the contraction of the intestinal smooth muscles (intestinal motility). Obviously with IBS-C the goal is to increase intestinal contraction, and decrease contraction with IBS-D. 

IBS shares common symptoms with Inflammatory Bowel Disease (IBD), although as the name suggests IBD symptoms are largely underpinned by inflammation, whereas in IBS there may only be a degree of inflammation underlying symptoms (*)

IBS and IBD are likely two different ends of the same spectrum, and have been suggested to exist on a sliding scale in terms of symptoms and their severity, particularly where inflammation is concerned. 

Symptoms of IBS

Symptoms can extend beyond just the digestive system, as typically an imbalance in the GI system can lead to nutrient deficiencies which can affect other aspects of bodily function, health and wellbeing. 

  • Abdominal Pain 
  • Bloating, Discomfort
  • Constipation, Diarrhea or both
  • Flatulence
  • Weight loss 
  • Depression 
  • Anxiety 
  • Fatigue 
  • Lessened Appetite 
  • Indigestion

Root Causes of IBS 

Believe it or not, there are functional imbalances that can underlie these symptoms. You don’t hear much about them, because conventional medicine isn’t acutely aware of them, and doesn’t test for them. However, there are functional tests that can identify them, in order to start addressing them. 


This is where the fundamental balance of microorganisms and bacteria have fallen out of harmony within the intestinal tract. An imbalanced composition of gut flora can underlie digestive symptoms related to IBS. 

Too much or too little of certain microorganisms can increase levels of inflammation in the gut (abdominal pain), cause immune reactions in response to certain foods (food intolerances), create excessive amounts of Methane, Hydrogen or Hydrogen Sulphide gasses (bloating & flatulence), and alter the contraction of the intestinal smooth muscle in either direction (constipation or diarrhea). 

Dysbiosis can happen after exposure to many different things:

  • Food Poisoning 
  • Antibiotics 
  • Environmental Pollutants - Pesticides, Herbicides, Fungicides etc 
  • Processed Foods, especially ones rich in white flour, refined sugar, additives and preservatives
  • Chronic Stress, severe bouts of Stress and/or Trauma 
  • Some Medications
  • Excessive Alcohol Intake

Intestinal Permeability (‘Leaky Gut’)

A leaky gut is another one of the functional mechanisms that can underpin symptoms of IBS, and can be addressed as a root cause. It is often something that develops overtime, and can be caused by exposure to a multitude of factors:

  • Antibiotics (overuse)
  • Processed Foods
  • Pesticides 
  • Excess Alcohol 
  • Chronic Stress 

The TL;DR of leaky gut is that things enter our bodies that aren’t meant to, as a result of an overly permeable intestinal wall. 

Foreign particles, of many shapes and sizes can pass into the body, and trigger the immune system. This can underlie many of the symptoms of IBS, including:

  • Food intolerances - improperly digested food proteins (such as gluten/gliadin, casein) can cause IgG immune responses, and lead to inflammation. 
  • Fatigue - immune flare ups use up energy, and can affect the cellular turnover of energy as a result of inflammation. 
  • Headaches, sleep disturbances, anxiety, depression and brain fog are partially driven by systemic inflammation originating in the gut. 
  • Gastrointestinal symptoms, including abdominal pain, constipation and diarrhea can result from inflammation in the gut (*)
  • Bacterial overgrowth - can cause excessive release of bacterial toxins that pass through the intestinal wall and create additional inflammation contributing to the above. 

Limiting exposure to the underlying causes, and managing diet are ways to keep symptoms under control, whilst cleaning up the bacterial ecosystem in the gut as well as repairing the gut wall to help reverse gut permeability. 

Clinical Endocannabinoid Deficiency

This is where we start getting into cannabinoids, which will shed some light on why using CBD for IBS is a no-brainer. 

If you’re saying to yourself WTF is an Endocannabinoid, and what is the Endocannabinoid system, then it’s worth getting a primer HERE. I’ll also give a short explanation here if you’d rather stick to this script. 

Endocannabinoids are basically our bodies own equivalent to cannabinoids that come from plants, like CBD. They act in a similar way to hormones, as messengers to keep the bodies systems constantly talking to one another and synchronized as a result. 

Clinical Endocannabinoid Deficiency is a hypothesis that suggests in IBS and a cluster of other conditions, a lack of endocannabinoids underlies many of the symptoms (*)

The long and short of Clinical Endocannabinoid Deficiency is that in the case of IBS, there is an insufficient amount of Endocannabinoids to keep the Gastrointestinal System in its sweet spot of normal, balanced functioning. This leads to many of the symptoms we listed above. 

Endocannabinoids are essential for keeping the gut ecosystem in check:

Endocannabinoids regulate the tight junctions in the intestinal wall, in order to keep foreign invaders from passing through from the GI tract into the bloodstream. A lack of Endocannabinoids can lead to a ‘leaky gut’

Endocannabinoids regulate the contraction of smooth muscles in the intestines. They are essential for maintaining the balance between too much and too little muscular contraction, in either direction. When endocannabinoids are out of balance, then this is where you can see chronic constipation or diarrhea. 

Endocannabinoids ‘talk’ to immune cells in the gut to keep them calm, and to manage levels of inflammation. A deficiency of Endocannabinoids can lead to unchecked levels of inflammation, and symptoms that arise from it such as abdominal pain, and also abnormal bowel functioning (C&D). 

Endocannabinoids ‘talk’ to gut microorganisms and can influence their configurations, in much the same way an NFL coach coordinates their players for certain plays in the game. The loss of this synchrony can mean certain microorganisms go rogue, and perpetuate inflammation and general gut function. 

Endocannabinoids regulate the sensation of pain in the intestinal tract, via regulating the sensitivity of neurons in the gut. A lack of endocannabinoids is related to visceral hypersensitivity (pain) in IBS (*)

Clinical Endocannabinoid Deficiency & Chronic Stress

It doesn't stop there, Endocannabinoids also control other bodily systems which have downstream consequences on how the digestive system works. 

Remember how we said that Chronic Stress and/or Trauma can be a root cause of IBS? Well, the link between those are Endocannabinoids. 

People who have been exposed to chronic stress, PTSD or trauma were found to have low levels of endocannabinoids (*)

Endocannabinoids are an essential braking mechanism that helps calm the nervous and hormonal systems when they are acting up in response to stress (*). When there is a Clinical Endocannabinoid Deficiency however, the braking power is reduced and stress hormones like adrenaline and cortisol are not effectively managed, and can go on to disrupt digestive function. That’s not all, a lack of endocannabinoids can open the door to depression and anxiety, too. 

When the body perceives that it is in imminent danger, the last thing it is going to devote energy to is to properly digest food. Instead it tells you to either suck it up (constipation) or to shit your pants and get the hell out of there. 

The problem is, when we have underlying trauma or a chronic stressor, they are constantly telling you (via stress hormones) that you are in danger, and therefore the body does not allocate appropriate resources to stimulate appetite, or instruct propper digestive function (via pro-appetite and pro-digestive hormones). 

You can hopefully start to see how stress plays a role in IBS, via stress hormones:

  • Cortisol and adrenaline reduce appetite (weight loss) 
  • Cortisol and adrenaline reduce stomach acid secretion (indigestion, weight loss)
  • Cortisol and adrenaline impair the proper contraction of intestinal muscles (constipation or diarrhea)
  • Cortisol and adrenaline increase gut leakiness (leaky gut)
  • Cortisol and adrenaline disrupt gut microorganism balance (dysbiosis)

For many people, it’s the psychological stress/anxiety which holds the key to breaking the cycle of IBS. This is the root cause for many, and correcting this can bring balance back to the endocannabinoid system, and the bodily functions it controls. 

Learning how to effectively manage stress, and resolving chronic stressors and trauma are the key to restoring the balance of endocannabinoids, which can help reduce cortisol and adrenaline, and instruct a ‘rest and digest’ response within the nervous and hormonal systems for proper digestion take once again take place. 

This process can take some time though. The good news is that we can use a ‘bandaid’ approach NOW to help bridge the gap, to temporarily support an increased level of endocannabinoids in the short term to manage symptoms. 

You are about to discover why using CBD oil for IBS could be an absolute game changer. 

Why Use CBD Oil For IBS?

So up to this point we have discussed the underlying root causes of IBS, and the various mechanisms that are out of sync that handle proper GI, nervous and endocrine (hormone) system function, and how a lack of endocannabinoids could be at the root of many of the symptoms related to IBS. 

Now we are going to cover exactly how using CBD for IBS may help correct many of these mechanisms, as we seek answers to the question: can CBD be used to treat IBS?


Typically to restore the balance of the gut microbiota, specific dietary protocols such as GAPS, SCD, KETO, or Candida are used to stop the growth of ‘bad’ microbes by limiting certain foods. 

Following this, antimicrobial herbs such as oregano, pau d’arco and berberine are used to kill off ‘bad’ microbes. 

CBD has also been found to be a very potent antibacterial and antifungal agent (*). This means it could help restore the balance of a healthy gut ecosystem by killing ‘bad’ microbes, which underlie many IBS symptoms. 

Taking CBD in capsule form is the best solution for this, as it directly interacts with those microbes in the intestines. 

Intestinal Permeability 

Reducing the ‘leakiness’ of the gut is essential for reducing levels of inflammation, which helps control gastrointestinal and psychological symptoms related to IBS. 

Limiting exposure to the things we outlined earlier, as well as managing stress is a good start to reducing intestinal permeability, but we can take it a step further with CBD. 

CBD has been found to inhibit the damage to intestinal cells by ‘bad’ microbes, as well as helping to bring each intestinal cell closer together to ‘tighten’ the gaps, reducing gut leakiness (*)

This has also been studied in humans, where a clinical trial found that CBD was able to reduce intestinal permeability, by reducing inflammation and also by ‘talking’ to the endocannabinoid system to directly tighten the intestinal barrier (*)

Again, CBD taken in capsule form means CBD directly passes through the intestinal tract, before entering the bloodstream. The study above also gave CBD orally, so in order to expect similar results we can replicate this method. 

Clinical Endocannabinoid Deficiency

One of the primary functions of CBD is to support the endocannabinoid system. Because cannabinoids are mirror images of our body's endocannabinoids, they can act as a transient replacement for restoring balance within the system. 

CBD can actually help restore the deficiency of certain endocannabinoids, as it is able to boost their production and inhibit their degradation. 

One endocannabinoid that CBD helps ‘boost’ levels of is called Anandamide. It is known as the bliss molecule, because it has powerful anti-anxiety, anti-depressant, anti-inflammatory, pain relieving, pro-sleep and most importantly pro-digestive functions. 

As we outlined above, endocannabinoid deficiency underlies many of the symptoms of IBS, because there is a lack of Anandamide. That’s why people with IBS often have depression, anxiety, inflammation, trouble sleeping, abdominal pain, and of course digestive issues (*)

CBD is effectively a one stop shop for IBS, because it helps restore imbalance within the core (endocannabinoid) system that controls all the other systems (digestive, etc). 

But make no mistake, this doesn’t mean that you have to take CBD for the rest of your life. CBD is simply there to help address the root imbalance temporarily, whilst addressing the reasons for a clinical endocannabinoid deficiency in the first place. 

Read more on the underlying causes of Clinical Endocannabinoid deficiency here. 

Constipation & Diarrhea

Does CBD affect bowel movements?

When we talk about constipation and/or diarrhea we are really talking about how slow or fast waste is moving through the intestines, which is based on how little or how much the intestinal muscles are contracting. 

With constipation the goal is to speed up the transit of waste, and increase intestinal contraction. 

With diarrhea the goal is to slow the transit of waste, and decrease intestinal contraction. 

Much of this will be helped by managing stress (because the nervous system is linked to intestinal contraction), and by reducing inflammation (through limiting certain foods, and including others). 

But CBD can also be helpful for constipation and/or diarrhea. 

CBD has been found to work in both directions when looking at either speeding up or slowing down what’s known as ‘intestinal motility’ (intestinal movement/contraction). 

CBD was shown to be an intestinal pro-kinetic (increasing intestinal movement), which may be helpful for those with constipation (*)

In contrast, CBD has also been shown to be an anti pro-kinetic, (reducing intestinal movement), which may be helpful to reduce diarrhea (*). Another way of putting this is that CBD can slow gut motility. 

Everyone's endocannabinoid system needs balancing in a unique way, and as a ‘tonic regulator’ it's CBD’s job to help restore balance, no matter which direction an imbalance has occurred (either constipation or diarrhea / alternating). 

So wehet

Stress & Anxiety

CBD is a powerful regulator of the nervous and hormonal systems that control stress. It’s the release of stress hormones cortisol and adrenaline that turns up the volume on stress and anxiety in the mind. 

CBD can actually blunt the release of stress hormones, by acting as a braking system for the nervous and hormonal systems. It activates the calming response within the vagus nerve, and helps the body shift more towards a ‘rest and digest’ state of relaxation. 

The result here is a greater feeling of wellbeing, and less feelings of stress and anxiety, which is widely reported in user experiences of CBD (*), (*), as well as clinical trials (*), (*)

CBD works specifically by filling the gap of Endocannabinoid deficiency here. Most people have sufficient levels of endocannabinoids to help put the brakes on the stress response, whereas in IBS and a few select other conditions that is not the case, which is why CBD can be a huge help. 

Studies: CBD for IBS

Only one study has examined the impact on how CBD helps with digestive issues, IBS specifically. This was only a survey as well, so more rigorous studies are needed to build upon these initial reports. CBD has however been studied in a more rigorous format for IBD (see research library).

The survey of active CBD users have shown that out of 3,506 participants, 366 used CBD for Gastrointestinal issues of which IBS was the most common (*). IBS users also used CBD for pain, mood issues and sleep problems. 

Interestingly, these users were using a Cannabis oil for IBS which also contained CBD, rather than simply a CBD-containing Hemp oil for IBS

Over 66% of those using CBD for IBS said that they felt either better or much better when asked how CBD affected their tiredness, abdominal pain, indigestion, bloating, diarrhea, acid reflux and constipation. 

Research on CBD and IBS

How to Take CBD For IBS

Without doubt the best way to take CBD for IBS is in capsule form. This is so the CBD can come into direct contact with the gastrointestinal system, as it passes through the intestines calming immune cells, reducing GI inflammation, killing microbes, and interacting with enteric (intestinal) nerves to control intestinal contraction, and also can help calm depression and anxiety through the gut <> brain connection. 

CBD Dosage For IBS

There is no specific dose for IBS, since dosing medications does not depend on what condition or disease an individual has, but an individual themselves. 

As an example, a 75kg person would not need the same dose as someone who is 120kg even if they both have IBS. Dosing is highly individual and is based on a myriad of factors, such as genetics influencing metabolism of substances such as CBD etc. 

The best way to figure out a CBD oil IBS dosage is to start low and go slow, which basically means start with a low dose and work your way up overtime to the point where you experience the strongest relief from symptoms. 

Check out our dosing guide for more info on that. 

How long it takes CBD to work for IBS also depends on which way CBD it taken, and individual factors such as body mass. You can learn more about that here.