Intestinal Gas
(Belching, Bloating, Flatulence)

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Intestinal gas facts

  • The usual cause of belching is excessive gas in the stomach that comes from swallowed air. However, discomfort in the abdomen for any reason also may cause belching. Therefore, belching does not always indicate the presence of excessive gas in the stomach.
  • Bloating is the subjective feeling that the abdomen is ful but does not necessarily mean that the abdomen is enlarged. Distention is the objective enlargement of the abdomen.
  • Continuous distention of the abdomen usually is caused by fluid, tumors, enlarged organs, or fat within the abdomen.
  • Intermittent distention of the abdomen may be caused by excessive formation of intestinal gas, as well as physical or functional obstruction of the intestines.
  • Flatulence (farting) results from the production of gas by bacteria within the intestines when they digest sugars and polysaccharides.
  • Excessive production of gas and increased flatulence may occur because of: (1) the greater ability of some bacteria to produce gas; (2) maldigestion or malabsorption of sugars and polysaccharides; and (3) bacterial overgrowth of the small intestine.
  • Belching, bloating/distention, and flatulence are evaluated with a medical history, simple abdominal X-rays, small intestinal X-rays, gastric emptying studies, ultrasound examination, computerized tomography (CT), magnetic resonance imaging (MRI), tests for maldigestion and malabsorption, and hydrogen breath tests.
  • The treatment of excessive intestinal gas depends on the underlying cause and may include dietary changes, medications that reduce the production of gas (for example, antibiotics), and medications that stimulate the muscles of the small intestine.
Medically Reviewed by a Doctor on 2/28/2014

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Intestinal Gas - Effective Treatments Question: What kinds of treatments have been effective for your intestinal gas?
Intestinal Gas - Causes Question: What was the cause of your intestinal gas?
Intestinal Gas - Bloating Causes Question: For some, it's eating a certain food. What is the usual cause of your bloating (intestinal gas)?
Intestinal Gas - Flatulence Causes Question: It may be embarrassing, but what is often the cause of your flatulence (intestinal gas)?
Gallstones and Bloating

Gum for Gas?

We all produce gas in our intestines, especially our colons, or, at least, our intestinal bacteria produce it, from undigested food. We are fortunate because the overwhelming majority of the gas that is formed by the bacteria is used up by other bacteria in the intestine.

Some people are more fortunate than others. All of the gas produced in their intestines is used up by bacteria, and they pass gas (fart) very little, that is, unless they eat foods that bacteria can use to form lots of gas like beans, that overwhelm even the most ardent, gas devouring bacteria. A small amount of intestinal gas is absorbed into the blood from the intestine and is eliminated in the breath. The gas that is not used up by bacteria or eliminated in the breath must be passed.

I recently underwent removal of a portion of my sigmoid colon for diverticulitis, and my intestines were keeping me from going home because they were not functioning properly, and the result was a distended abdomen...