Colon (large intestine)

The colon is the large intestine, the final section of the digestive tract that absorbs water and salts from digested food and forms and stores stool.

It runs from the end of the small intestine to the rectum and is home to trillions of bacteria that ferment fiber, produce short-chain fatty acids and vitamins, and shape immune function throughout the body. Its wall contains muscle layers that move contents along, a nerve network called the enteric nervous system, and a lining that renews itself every few days. Common conditions include irritable bowel syndrome, inflammatory bowel disease in the forms of ulcerative colitis and Crohn's disease, diverticular disease, polyps and colorectal cancer.

Cannabinoid receptors are abundant in the colon, on nerve cells, immune cells and the lining, and the endocannabinoid system participates in regulating motility, secretion and inflammation there. Cannabinoids have been studied in animal models of colitis and in small human trials for inflammatory bowel disease, and orally consumed cannabinoids are absorbed partly in the colon. That research is early, and no cannabinoid has an approved use for any colon condition.