Endocannabinoid and cannabinoid-like fatty acid amide levels correlate with pain-related symptoms in patients with IBS-D and IBS-C: a pilot study

PLoS One. 2013 Dec 27;8(12):e85073. doi: 10.1371/journal.pone.0085073. eCollection 2013.


Aims: Irritable bowel syndrome (IBS) is a functional gastrointestinal (GI) disorder, associated with alterations of bowel function, abdominal pain and other symptoms related to the GI tract. Recently the endogenous cannabinoid system (ECS) was shown to be involved in the physiological and pathophysiological control of the GI function. The aim of this pilot study was to investigate whether IBS defining symptoms correlate with changes in endocannabinoids or cannabinoid like fatty acid levels in IBS patients.

Methods: AEA, 2-AG, OEA and PEA plasma levels were determined in diarrhoea-predominant (IBS-D) and constipation-predominant (IBS-C) patients and were compared to healthy subjects, following the establishment of correlations between biolipid contents and disease symptoms. FAAH mRNA levels were evaluated in colonic biopsies from IBS-D and IBS-C patients and matched controls.

Results: Patients with IBS-D had higher levels of 2AG and lower levels of OEA and PEA. In contrast, patients with IBS-C had higher levels of OEA. Multivariate analysis found that lower PEA levels are associated with cramping abdominal pain. FAAH mRNA levels were lower in patients with IBS-C.

Conclusion: IBS subtypes and their symptoms show distinct alterations of endocannabinoid and endocannabinoid-like fatty acid levels. These changes may partially result from reduced FAAH expression. The here reported changes support the notion that the ECS is involved in the pathophysiology of IBS and the development of IBS symptoms.

Publication types

  • Clinical Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Amides / blood*
  • Constipation / blood
  • Diarrhea / blood
  • Endocannabinoids / blood*
  • Fatty Acids / blood*
  • Female
  • Humans
  • Irritable Bowel Syndrome / blood*


  • Amides
  • Endocannabinoids
  • Fatty Acids

Grant support

This work was supported by the University of Calgary Research Grant Committee (to MS), the Iuventus Plus program of the Polish Ministry of Science and Higher Education (0119/IP1/2011/71 and 0107/IP1/2013/72 to JF), and the Deutsche Forschungsgemeinschaft (STO 645/6-1 to MS). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.