What are the key diagnostic criteria for Irritable Bowel Syndrome (IBS) in adults according to NICE guidelines?

A diagnosis of IBS should be considered only if the person has abdominal pain or discomfort that is either relieved by defaecation or associated with altered bowel frequency or stool form ¹.

It should be accompanied by at least 2 of the following 4 symptoms: altered stool passage (straining, urgency, incomplete evacuation), abdominal bloating (more common in women than men), symptoms made worse by eating, and passage of mucus ¹.

Healthcare professionals should assess and exclude 'red flag' indicators such as signs of cancer or inflammatory markers for inflammatory bowel disease, before confirming the diagnosis ¹.