Irritable Bowel Syndrome (IBS) is one of the most common complaints in the western world. Around 50% of all gastrointestinal complaints and half of all GP referrals are due to IBS. Irritable bowel syndrome is also known by many other names, such as spastic colon, mucous colitis, functional bowel disorder, dyspeptic diarrhoea, spastic constipation, anxiety and GI syndrome, and nervous bowel.
It affects 24% of all women and 19% of all men, usually developing in late adolescence or early adulthood. Before the menopause, more women than men present with IBS; after the menopause the numbers are about equal. The condition is characterised by intermittent periods of constipation or diarrhoea, often accompanied by bloating and/or abdominal pain, mucous in stools and bowel rumbling.
Irritable bowel syndrome needs to be distinguished from conditions with similar symptoms such as celiac, colorectal cancer, infective diarrhoea, diverticular disease, carcinoid syndrome, gallstones, appendicitis and inflammatory bowel disease (IBD).