Irritable Bowel syndrome


Irritable bowel syndrome (IBS) can be a painful, disabling but poorly understood chronic abdominal illness, associated with bowel disturbance and a range of other bodily and psychological symptoms. IBS may be regarded as one component a spectrum of medically unexplained illnesses. As such, there is a strong overlap with other illnesses such as chronic fatigue syndrome, fibromyalgia syndrome and functional dyspepsia.

For most people, IBS is a fairly benign condition that tends to recur at times of stress and change, but for some it is profoundly disabling, ruling their lives and confining them to their homes.


Last reviewed October 2017 by Dr Nick Read, Psychoanalytical Psycotherapist and previous gastroenterologist, nutritionist and adviser to the IBS Network. 

Although great care has been taken in the compilation and preparation of all entries to ensure accuracy, we cannot accept responsibility for any errors or omissions. Any medical information is provided is for education/information purposes and is not designed to replace medical advice by a qualified medical professional.

What are the symptoms?

Individuals with IBS have frequent attacks of abdominal pain or bloating, which are associated with disturbances in defecation (voiding of waste matter or faeces from the bowel), which might be either constipation, diarrhoea or a combination of the two.  In addition to bowel symptoms, sufferers also frequently complain of a variety of other symptoms, especially fatigue, breathlessness, headaches, indigestion, backache, anxiety and depression. Symptoms are commonly brought on by life changes and difficult life situations, but they may also be triggered by food.

What are the causes?

IBS can be triggered by an attack of gastroenteritis (especially if this occurs with anxiety and depression), a traumatic event or situation or administration of large or frequent doses of antibiotics.

Studies have shown enhanced gastrointestinal motility and sensitivity, enhanced immune responses, a leaky gut, changes in the composition of bacteria in the large bowel and alterations in the interaction between the brain and gut, but such changes often occur together and may represent a resetting of brain gut function. This can make people with IBS very sensitive to certain foods, especially fats, coffee, wheat, milk, fruits, vegetables and cereal fibre.

How is it diagnosed?

There is no specific test for IBS. It is diagnosed by a combination of typical abdominal and bowel symptoms, and the absence of any indications of other chronic abdominal diseases (evacuation of blood or mucus, fever, weight loss, anaemia). In particular, Coeliac Disease and inflammatory bowel disease need to be excluded by tests on samples of blood or faeces. In children, allergies also need to be excluded. 

How is it treated?

Symptoms may be eased with antispasmodics, such as Colofac and Spasmonal, and with bowel regulators, such as Imodium and Fybogel. Dietary restriction of fruits and vegetables can alleviate pain bloating, restriction of milk and other dairy products may reduce diarrhoea and reducing intake of fat and coffee can help to prevent abdominal pain. Identification and management of stressful situations can be very helpful in reducing symptoms. Psychological therapies, hypnotherapy and complementary therapy may be helpful when other measures fail.

Inheritance patterns and prenatal diagnosis

IBS can tend to run in families, but there is no specific combination of genes for IBS. The association is more likely to be that families share the same diet, experience the same stress and harbour the same bacteria in the colon.

Is there support?

The IBS Network

Tel: 0114 272 32 53

The IBS Network is the national charity registered in England and Wales no. 1173208 supporting people living with Irritable Bowel Syndrome. Our mission is to provide information, advice and support for people living with IBS and those who care for them and to work alongside health care professionals to facilitate self-care.  

Group details last updated October 2017.

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