Common medical conditions explained: Irritable Bowel Syndrome (IBS)

    6 January 2020

    What is it?

    Irritable Bowel Syndrome (IBS) is a term used to describe a set of unpleasant and debilitating symptoms that affect the bowels. It is often considered a ‘diagnosis of exclusion’ meaning doctors diagnose it when all other likely conditions have been ruled out. It’s incredibly common, with between 10 and 20 per cent of the population having it at any one time. The symptoms include stomach cramps, bloating, diarrhoea and constipation. Excessive flatulence, feeling sick, bladder problems and passing mucus from your back passage are other symptoms. There is considerable variation in the symptoms from person to person, with the symptoms often coming and going. Some people find the symptoms ease after going to the toilet, while for others they remain in pain or struggle to open their bowels despite feeling that they need to. Stress and emotions play a big part, with people often finding that it flares up when they are worried, nervous or anxious.

    What causes it?

    While there’s no clear cause for the condition, it can follow an attack of gastroenteritis, a course of antibiotics or very upsetting or traumatic events. This seems to disrupt the normal functioning of the gut, stimulating the gut immune systems, causing inflammation and depleting bacteria in the gut. This leads to the gut becoming very sensitive. Despite the crippling symptoms, all too often these patients are dismissed once they have a diagnosis. Part of the problem is that many of the symptoms of IBS mimic other conditions meaning that getting a diagnosis often takes a long time as other conditions have to be explored and discounted first. There is no specific test for IBS and diagnosis is made on the symptoms.

    How is it treated?

    IBS is often a life-long condition and treatment consists of managing the symptoms. It is usually first treated by making lifestyle modifications and people often find that changing their diet can help. Keeping a food diary and monitoring what you eat and when flares up occur can help identify food to avoid. People are often advised to think about the amount of fibre they are having in their diet. There are two types – soluble (in oats, barley and fruit) and insoluble (in whole grain bread, bran and cereals). Some find cutting down the insoluble fibre in their diet if they are prone to diarrhoea, or increasing the soluable fibre if they are prone to constipation helps. There is also a particular diet called the FODMAP (fermentable oligosaccharides, disaccharides, monosaccharides and polyols) diet. This involves avoiding various foods that are high in FODMAPs. This needs to be done under the guidance of a dietician. Psychotherapy to hep reduce anxiety and stress can also be very helpful.

    What can the patient do?

    The IBS Network – the main UK charity for sufferers – have a great deal of advice on their website ( on what patients can do to help themselves. Eating regularly helps as can reducing alcohol and caffeine. If you have wind or bloating, eating whole oats or linseed can also help. There is very good evidence to suggests that probiotics can help alleviate symptoms. It’s thought that this helps to decrease the sensitivity of the gut by repopulating it with ‘good’ bacteria that help the gut function efficiently and prevent the inflammation. However, many of the commercial probiotics that are on sale in supermarkets or health food shops are not very effective. A comprehensive study conducted in 2015 on the major brands to see which of them could actually deliver live, viable bacteria into the gut found most do not. Only two probiotics – Symprove and VSL#3 did, so these are currently the ones that are recommended.