Abdominal bloating and distension: what is the role of the microbiota.

Most patients with irritable bowel syndrome complain of a sensation of an increase in pressure within their abdomen during the course of the day which is called bloating and, in approximately half of these individuals, this symptom is accompanied by an actual increase in abdominal girth, which is referred to as distension. The pathophysiology of these two phenomena is somewhat different and it is now recognised that a whole variety of overlapping mechanisms are involved. Some of these are potentially amenable to treatment by modification of the bacterial flora of the gut and this article reviews the evidence for this.