Cannabidiol (CBD) is getting a lot of attention as a natural solution for anxiety, pain, and sleep issues. But some people also use CBD products for less common conditions, such as irritable bowel syndrome (IBS).
Although mild IBS can be controlled with dietary changes and medication, many sufferers, and especially those with more serious cases, turn to alternative treatments such as cannabis and CBD oil.
Early research highlights CBD as a promising candidate for alleviating IBS symptoms.”
There isn’t a lot of research looking at the use of CBD for IBS. Still, there’s some evidence that CBD may help by relieving related symptoms such as anxiety, pain, inflammation, and nausea, as well as influencing gut function directly by interacting with the endocannabinoid system.
Here’s a look at the potential benefits of CBD for IBS, according to scientific research.
IBS is a common digestive disorder that affects the large intestine. It’s characterized by abdominal pain, constipation or diarrhea, and other digestive symptoms.
The identifying feature of IBS, and what separates it from the related irritable bowel disease (IBD), is that there isn’t any underlying tissue damage.
Researchers estimate that IBS affects about 10-15% of the world’s population. ¹ It’s a chronic disorder with symptoms that can flare up and range from mild to severe.
Researchers have yet to identify the exact causes of IBS but abnormal intestinal muscle contractions and altered communication between the brain and gut appear to be involved.
Additionally, psychological stress, especially in early life and adulthood, seems to play an important role in the development of IBS. ²
There are four subtypes of IBS: ³
- IBS-D: IBS that’s mostly accompanied by symptoms of diarrhea.
- IBS-C: IBS with predominant constipation.
- IBS-M: Mixed IBS with bouts of both constipation and diarrhea.
- IBS-U: Unclassified IBS that doesn’t fit into the other categories.
IBS Symptoms & Pathology
The most common symptoms of IBS are abdominal pain and discomfort alongside diarrhea or constipation. IBS can also cause bloating, gas, cramping, and other digestive issues.
Sufferers often report the symptoms appearing or getting worse after eating and disappearing after having a bowel movement.
Can CBD Help With IBS?
According to research, there are several ways that CBD can help with IBS.
First and foremost, CBD may regulate gut motility — contractions of the muscles of the digestive tract. Abnormal intestinal motility plays a major role in IBS and typically leads to either diarrhea or constipation.
Several studies in mice found that CBD can normalize both intestinal hypermotility (excessive digestive muscle movement) and hypomotility (reduced movement) caused by inflammation. ⁴ ⁵ ⁶
Another less obvious way that CBD may be beneficial is through its anxiolytic (anxiety-reducing) and antidepressant properties. ⁷ ⁸
Multiple studies have shown that people with IBS have higher rates of anxiety, depression, and other mental health issues, highlighting the brain-gut connection implicated in the condition. ⁹
CBD can also help by relieving abdominal pain, one of the main symptoms of IBS. However, the findings for visceral pain — a type of pain that includes abdominal pain — are not yet conclusive.
One older study conducted in 1988 found that CBD relieved pain in mice during a writhing test that’s used for measuring visceral pain but a more recent study done in 2009 using a similar test reported that only THC and CBN, but not CBD, had an analgesic (pain-relieving) effect. ¹⁰ ¹¹
Additionally, CBD has been shown to reduce nausea in animals, which is another possible symptom of IBS. ¹²
Lastly, CBD’s well-documented anti-inflammatory effects may help too, since emerging research indicates that inflammation could also be involved in IBS. ¹³ ¹⁴
The Endocannabinoid System and IBS
The body’s endocannabinoid system (ECS) plays a major role in gut health and researchers theorize that compounds capable of interacting with it (such as CBD) may help with IBS.
This network of cannabinoid receptors (CB1 & CB2), endocannabinoids produced by the body, and special enzymes work to maintain homeostasis: an internal state of healthy balance.
To achieve that, the ECS regulates many essential functions, including those involved in IBS, namely mood, anxiety, nausea, gut function, and pain.
On top of that, the ECS also modulates the so-called “gut-brain axis”: the direct communication between the brain and the digestive tract which may explain the back-and-forth link between anxiety, depression, stress, and other mental health issues and digestive symptoms. ¹⁵
Studies have also shown that activation of both CB1 and CB2 receptors reduces gut motility, intestinal peristalsis (wave-like muscle contractions that move food through the digestive tract), as well as visceral pain. ¹⁶ ¹⁷ ¹⁸
More importantly, there’s growing evidence that a dysfunction of the endocannabinoid system called clinical endocannabinoid deficiency (CED) is the culprit behind some cases of IBS and other chronic, difficult-to-treat disorders like migraines. ¹⁹
To illustrate this, one study found that compared to healthy adults: ²⁰
- Those with IBS-D had higher levels of the endocannabinoid anandamide and lower levels of two endocannabinoid-like compounds: OEA and PEA.
- Those with IBS-C had higher OEA but reduced colon levels of FAAH, an enzyme that breaks down anandamide.
Meanwhile, another study found that certain genetic variations of the cannabinoid receptor 1 (CB1) gene were associated with IBS. ²¹
Researchers also theorize that some of these and other abnormal changes were seen in the ECS of people with IBS may be linked to the effects of chronic stress, which happens to be one of the causal factors of the condition.
Taken together, the available evidence suggests that ECS dysfunction may play a significant role in IBS and that compounds that target this system could be beneficial.
That includes CBD, which can influence the ECS in multiple ways, most notably by suppressing the FAAH enzyme, which in turn prolongs the effects of the endocannabinoid anandamide. ²²
That’s why a 2020 review paper mentioned CBD as one of several “agents capable of modulating the ECS” and providing a “strategy worth attempting even first-line treatment for IBS patients.” ²³
What Does the Research Say?
Unfortunately, there aren’t any human studies looking at the use of CBD for IBS.
However, one 2020 study of U.S. patient data did find that IBS patients who used cannabis were less likely to require medical help than those who didn’t, suggesting that cannabinoids may have beneficial effects on the condition. ²⁴
There’s also a clinical trial underway in the Netherlands looking at whether CBD-infused chewing gum can alleviate the symptoms of IBS.
Additionally, multiple studies have demonstrated that CBD has pain-relieving properties that may help with IBS abdominal pain.
This includes a 2015 review of 79 clinical studies which concluded that “there was moderate-quality evidence to support the use of cannabinoids for the treatment of chronic pain.” ²⁵
There’s also some evidence that CBD can improve irritable bowel disease (IBD):
- In a 2018 study, unlike a placebo, CBD-rich cannabis extract improved IBD symptoms and quality of life. ²⁶
- Another 2018 reported that CBD-rich cannabis oil (15% CBD/4% THC) reduced disease severity and improved quality of life in people with Crohn’s disease (a type of IBD), unlike placebo treatment. ²⁷
Although IBD is a separate digestive condition that’s more serious than IBS, there’s growing evidence that the two may be closer related than previously thought. ²⁸ As such, these findings suggest that CBD could help with IBS as well.
To summarize, although there are some promising findings, high-quality studies focusing specifically on the effects of CBD in people with IBS are still needed.
How Much CBD Should I Take for IBS?
The right dosage of CBD for IBS varies between individuals. It’s influenced by many factors, including your body weight, genetics, the severity of your IBS symptoms, and the type of CBD product you’re using.
That’s why the recommended approach for finding the right amount of CBD is to “start low and go slow.” ²⁹
You should begin with a small CBD dose (10-15 mg), wait a few hours to see the effects, and gradually increase until you start to experience the desired relief. Once you find the CBD dosage that works, you can stick to it. While everyone has a different preference, we personally believe full spectrum CBD extract is best as it allows for the entourage effect.
Are There Any Side Effects?
According to research, CBD along with other cannabinoids from the hemp and cannabis plant are generally safe, well-tolerated compounds. Although it can cause some side effects, they’re usually mild. The most common side effects of CBD are: ³⁰
- Tiredness and drowsiness
- Diarrhea and nausea
- Dry mouth
- Low blood pressure
- Changes in appetite or weight
Besides, these side effects have only been reported in studies using high doses of pure CBD.
That means the average person is less likely to experience them. This is even more true when considering that many people opt for whole-plant preparations, which may be even less prone to causing side effects. ³¹
Early research highlights CBD as a promising candidate for alleviating IBS symptoms.
Better yet, if the endocannabinoid deficiency theory proves to be correct, CBD could be one of the few treatment options that not only relieve IBS symptoms but target the root cause of the condition.
Having said that, the key issue is the lack of human studies looking specifically at the use of CBD for IBS. Much more research is still needed to confirm the benefits of CBD for treating IBS in humans.
Most of the existing evidence comes from animal studies or trials of CBD for other conditions. We need to wait for the results of rigorous clinical studies before there’s real proof that CBD can improve IBS.
Still, considering that CBD is an exceptionally safe, natural compound, there’s no harm in giving it a try, especially for IBS sufferers who haven’t seen positive results from prescription medications and dietary changes.