Pathophysiology, evaluation, and treatment of bloating: hope, hype, or hot air?

Abstract

Abdominal bloating is commonly reported by men and women of all ages. Bloating occurs in nearly all patients with irritable bowel syndrome, and it also occurs in patients with other functional and organic disorders. Bloating is frequently disturbing to patients and frustrating to clinicians, as effective treatments are limited and are not universally successful. Although the terms bloating and abdominal distention are often used interchangeably, these symptoms likely involve different pathophysiologic processes, both of which are still not completely understood. The goal of this paper is to review the pathophysiology, evaluation, and treatment of bloating and abdominal distention.

Keywords: Abdominal pain; abdominal distention; antibiotics; bloating; fiber; fructose; irritable bowel syndrome.

Figure 1

The physiology of intestinal gas, which develops primarily from food and drinks that are ingested or swallowed. Large amounts of carbon dioxide (CO₂) are produced in the small intestine as a byproduct of digestion, and much is reabsorbed in the small intestine. Hydrogen (H₂) and CO₂ are produced in large amounts within the colon, although much is reabsorbed. Methanogenic bacteria consume H₂ and release methanethiol and hydrogen sulfide. CH₄=methane; HCl=hydrochloric acid; HCO₃^–=hydrogen carbonate; N₂=nitrogen; O₂=oxygen.