Irritable Bowel Syndrome (IBS) is an unexplained gut illness that comprises abdominal pain, bloating, diarrhoea and constipation, for which there is no clear cause.   It also includes a variety of other symptoms that affect other organs and regions of the body and it overlaps with other unexplained illnesses, notably Chronic Fatigue Syndrome, Fibromyalgia and Functional Dyspepsia.  Anxiety and depression are also very common, suggesting that IBS is the visceral expression of an illness that affects both mind and gut. 

IBS may start with an attack of gastroenteritis and/or a traumatic experience.  Both may lead to depletion of colonic bacteria, increases in gut permeability, excitation of the gut immune system and changes in the emotional centres of the brain and their connections with the gut, resetting the gut control systems to be more sensitive to diet and stress (food and mood).  Reducing intake of fat and fermentable sugars (FODMAPs) in the diet may calm IBS symptoms as can a more balanced, measured and relaxed life style.  Medications, which include antispasmodics and bowel regulators offer relief for specific symptoms. 

IBS often fluctuates according to what is happening in a person’s life.  Thus it is important to help people understand the context of their illness and help them deal with it.  Self-help involves diet, stress reduction and over the counter medication for relief of symptoms, while changing life situation and perception and adopting a positive focus may give rise to longer term remission.