IBD is considered an organic disorder because the disease affects both the tissues and the function of the intestinal tract. Irritable bowel syndrome (IBS), on the other hand, is considered a functional disorder because the intestines aren’t damaged, but they don’t function normally. Whereas IBD is likely an autoimmune disease, IBS is thought to involve the gut-brain axis and the enteric nervous system (nerves that control the GI tract independent of the brain.) Abdominal pain and bloating can occur in both disorders, but more serious symptoms — like bloody stool — would only be present in IBD.[1]
References
- ^Drossman DAFunctional Gastrointestinal Disorders: History, Pathophysiology, Clinical Features and Rome IV.Gastroenterology.(2016-Feb-19)