Exploring the benefits of medical cannabis for gastroenterological conditions

What are gastroenterological conditions?

Gastroenterological conditions - also known as gastrointestinal conditions or simply digestive diseases - refer to conditions that affect the gut or digestive system. This encapsulates a large number of conditions, the most common of which are inflammatory bowel disease (IBD) (which includes both Crohn’s disease and ulcerative colitis) and irritable bowel syndrome (IBS). 

These conditions are associated with a wide range of symptoms, including abdominal pain, constipation, diarrhoea, weight loss, blood in stools, fatigue, and anaemia. 

Inflammatory bowel disease

As mentioned above, IBS refers to two common gastroenterological conditions: Crohn’s disease and ulcerative colitis in addition to other forms of the condition. It is estimated that around 1 in 123 people in the UK (more than half a million people) are living with IBD. 

It is a lifelong condition that requires ongoing maintenance and treatment to limit the severity of symptoms. Diagnosis of IBD can be difficult as many of the symptoms are similar to those of other conditions. 

Crohn’s disease

Crohn’s disease is characterised by inflammation of part of the digestive system. It can affect people of all ages, but most commonly develops in childhood or early adulthood. The exact cause of Crohn’s disease is not fully understood; however, several factors are believed to play a role in the condition. For example, some evidence indicates that genes, smoking, previous contraction of a stomach bug, and having an abnormal balance of gut bacteria may be associated with Crohn’s disease. 

What are the symptoms of Crohn’s disease?

Symptoms of Crohn’s disease can be constant or come and go as “flare-ups” followed by periods of remission. The most common symptoms of Crohn’s disease include:

• Diarrhoea
• Stomach aches and cramps - usually in the lower-right part of the stomach
• Blood in your stool
• Weight loss
• Fatigue

Some patients may also experience additional extraintestinal symptoms, including high temperatures, joint pains, mouth ulcers, and painful, swollen skin patches.

What are the treatments for Crohn’s disease?

There is no cure for Crohn’s disease but several treatment options may help to control the associated symptoms. 

Pharmacological approaches to Crohn’s disease usually include the use of steroids which can help to reduce inflammation in the digestive system. While steroids are often effective, they are also associated with undesirable side effects such as indigestion, sleep disturbance, weight gain, and an increased risk of infections. 

Some patients may also be prescribed immunosuppressants or be advised to follow a special diet. When these approaches fail to achieve satisfactory symptom relief, biological medicines or surgery may be considered.

Ulcerative colitis

Ulcerative colitis is another form of IBD in which the large intestine (colon) and rectum become inflamed. This can include the development of ulcers on the colon’s lining which may bleed and release pus. Ulcerative colitis may is also associated with an increased risk of developing bowel cancer and poor growth and development in children and young people. 

The cause of ulcerative colitis is not fully understood, however, it is believed to be an autoimmune condition. This means that the body’s immune system mistakes bacteria inside the colon as a threat and attacks healthy tissue. The development of ulcerative colitis may be linked to both genetic and environmental factors. 

What are the symptoms of ulcerative colitis?

Like Crohn’s, ulcerative colitis is often characterised by flare-ups and periods of remission. During flare-ups, symptoms can include:

• Diarrhoea, which may contain blood, mucus or pus
• Abdominal pain
• Frequently needing to poo
• Fatigue
• Loss of appetite
• Weight loss

Some individuals may also experience extraintestinal symptoms such as swollen joints, mouth ulcers, eye irritation, and swollen fat under the skin (known as erythema nodosum). 

What are the treatments for ulcerative colitis?

There is no cure for ulcerative colitis and treatment can depend on the severity of symptoms and frequency of flare-ups. However, treatment for ulcerative colitis usually involves the use of various medicines, including aminosalicylates (5-ASAs) and corticosteroids to help reduce inflammation, and immunosuppressants to reduce the activity of the immune system.

While these medicines are typically helpful in reducing symptoms associated with inflammation, they can also associated with undesirable side effects. In particular, even short-term use of corticosteroids can cause mood changes, sleep disturbance, increased appetite and weight gain, and acne. 

In the case of more severe flare-ups, treatment in hospital is often recommended to minimise the risk of more serious symptoms. This may include the use of intravenous corticosteroids, immunosuppressants, and biologic medicines. In severe cases where patients experience frequent flare-ups, surgery to remove the colon (a colonectomy) may be performed.

Irritable bowel syndrome (IBS)

Irritable bowel syndrome (IBS) is a common, long-term condition that affects the digestive system. It is characterised by a number of intestinal symptoms that occur together. While the cause of IBS is not fully understood, recent research indicates that many of its symptoms are linked to hypersensitivity on the nerves in the walls of the gastrointestinal tract. 

There are four subcategories of IBS:

• IBS-D - mostly characterised by diarrhoea and abdominal discomfort.

• IBS-C - mostly characterised by constipation and abdominal discomfort.

• IBS-mixed - alternating loose stools and constipation with abdominal discomfort. 

• Undefined subtype (IBS-U) - symptoms vary. 

What are the symptoms of IBS?

The main symptoms of IBS are:

• Abdominal pain or cramps which are usually worse after eating and improve after clearing the bowels
• Diarrhoea
• Constipation
• Bloating

Some IBS symptoms may be triggered by certain foods and drinks, stress, and anxiety. Other symptoms also associated with IBS can include: 

• Flatulence
• Mucus in stool
• Tiredness
• Nausea
• Bowel incontinence
• Backache or chronic pelvic pain

What are the treatments for IBS?

Again, there is no cure for IBS. Therefore, the aim of treatment is to provide relief from your symptoms. This can include dietary changes, pharmacological interventions, and behavioural approaches that are tailored to each individual. 

Some patients find that their symptoms improve when making certain dietary changes, such as avoiding caffeine, fatty foods, excessive carbohydrates, or foods that are high in lactose, fructose, and sorbitol. For example, some may benefit from the low FODMAPs diet.

However, in many cases, further intervention is required to adequately manage symptoms. Medications for irritable bowel syndrome can include smooth muscle relaxants, antidiarrhoeal medicines, laxatives, antibiotics, and low-dose antidepressants.

Medical cannabis treatment for gastroenterological conditions

Many people with one of the gastroenterological conditions outlined above find it difficult to manage their symptoms using conventional therapies, or are unable to tolerate the associated side effects. This leaves many individuals looking for alternative treatments for inflammatory bowel disease or irritable bowel syndrome. 

For example, the potential medical cannabis for Crohn’s disease, ulcerative colitis, and IBS has become a growing area of interest. Indeed, the endocannabinoid system (ECS) - a regulatory system expressed throughout the human body - has been found to play a significant role in maintaining homeostasis in the digestive system. 

Some evidence indicates that cannabinoid therapy may be beneficial in slowing intestinal motility, maintaining healthy pH levels in the digestive tract, and achieving a healthy gut microbiome. But what about evidence for the use of medical cannabis in specific conditions such as Crohn’s disease, ulcerative colitis, and IBS?

Medical cannabis for IBD

Several clinical and observational studies have explored the potential of medical cannabis for IBD, including both Crohn’s disease and ulcerative colitis. Real-world data from UK medical cannabis patients indicates that medical cannabis treatment is associated with short-term improvements in refractory symptoms of Crohn’s disease and ulcerative colitis and quality of life. 

Another study, published in 2013, found that the inhalation of THC-rich cannabis flower was associated with significant clinical, steroid-free benefits in 10 of 11 patients with Crohn’s disease. Moreover, a 2021 randomised controlled trial concluded that treatment with THC-rich cannabis “induced clinical remission and improved quality of life in patients with mild to moderately active ulcerative colitis.”

Medical cannabis for IBS

Several studies have also yielded promising findings concerning medical cannabis treatment for IBS. A 2020 study of patients with IBS found that inpatient healthcare utilisation was lower among those who used cannabis, indicating potentially beneficial effects of the therapy. 

Another 2020 survey of Australian IBS patients found that over a quarter of respondents were current or past users of medical cannabis, and 92.7% endorsed cannabis as effective in symptom management. Numerous studies have also found that medical cannabis may help to relieve symptoms of IBS.

Dr David Tang, medical cannabis prescriber and Releaf's Clinical Director, notes:

"There is increasing evidence that medical cannabis can reduce the intensity of symptoms in patients with inflammatory bowel disease, albeit without altering what the condition looks like under the microscope. 

“Irritable bowel syndrome similarly, although a distinct condition from both Crohn’s and Ulcerative Colitis, can be calmed down considerably by means of cannabinoid therapy.”

Moreover, patients diagnosed with gastroenterological conditions often experience comorbid conditions such as anxiety, depression, and chronic pain, for which medical cannabis treatment may also be useful.

Final thoughts

More high-quality clinical evidence is required to better understand the role of medical cannabis in the treatment of gastroenterological conditions. Nonetheless, current findings indicate that they may be beneficial for patients who have been unable to achieve relief with other treatments. 

Medical cannabis can now be considered in the treatment of gastroenterological conditions, including Crohn’s disease, ulcerative colitis, and IBS, when at least two conventional therapies have proven ineffective. Find out more about medical cannabis prescriptions for IBD and IBS at Releaf.