UEG Week: Cannabis significantly improves the symptoms of Crohn’s disease despite having no effect on gut inflammation

In the first study of its kind, cannabis oil has been shown to significantly improve the symptoms of Crohn’s disease and the quality of life of sufferers but, contrary to previous medical thinking, has no effect on gut inflammation.

In a randomised, placebo-controlled study, researchers from Israel have shown that cannabis can produce clinical remission in up to 65% of individuals after 8 weeks of treatment, but that this improvement does not appear to result from a dampening down of the underlying inflammatory process.

Speaking at UEG Week 2018 in Vienna, lead researcher, Dr Timna Naftali explained, “Cannabis has been used for centuries to treat a wide range of medical conditions, and studies have shown that many people with Crohn’s disease use cannabis regularly to relieve their symptoms.It has always been thought that this improvement was related to a reduction in inflammation in the gut and the aim of this study was to  investigate this.” 

The Israeli team recruited 46 people with moderately severe Crohn’s disease, and randomized them to receive 8 weeks of treatment with either cannabis oil containing 15% cannabidiol and 4% tetrahydrocannabinol or placebo. Symptom severity and quality of life were measured before, during, and after treatment using validated research instruments. Inflammation in the gut was assessed endoscopically and by measuring inflammatory markers in blood and stool samples. 

After 8 weeks of treatment, the group receiving the cannabis oil had a significant reduction in their Crohn’s disease symptoms compared with the placebo group, and 65%met strict criteria for clinical remission (versus 35% of the placebo recipients). The cannabis group also had significant improvements in their quality of life compared with the placebo group.

“We have previously demonstrated that cannabis can produce measurable improvements in Crohn’s disease symptoms⁴ but, to our surprise, we saw no statistically significant improvements in endoscopic scores or in the inflammatory markers we measured in the cannabis oil group compared with the placebo group,” said Dr Naftali. “We know that cannabinoids can have profound anti-inflammatory effects but this study indicates that the improvement in symptoms may not be related to these anti-inflammatory properties.”

Looking ahead, the research group plans to explore further the potential anti-inflammatory properties of cannabis in the treatment of inflammatory bowel disease. “There are very good grounds to believe that the endocannabinoid system is a potential therapeutic target in Crohn’s disease and other gastrointestinal diseases,” said Dr Naftali. “For now, however, we can only consider medicinal cannabis as an alternative or additional intervention that provides temporary symptom relief for some people with Crohn’s disease.’