Irritable bowel syndrome, (IBS) is a common functional disorder of the gut that can be quite disabling to patients. The most common symptoms of IBS are abdominal pain or discomfort along with erratic changes in bowel habit of diarrhoea, constipation or a mixture of the two (referred to as IBS subtypes). Despite much research efforts to further understand the pathophysiology of IBS; as yet no specific biomarkers/definitive measurements have been identified that can be use to aid the diagnosis and reduce the need for unnecessary, unpleasant and expensive tests.