How are gas problems evaluated?

Although gas is very common, at times medical evaluation is necessary. Weight loss, anemia, fevers, diarrhea, or blood in the stool should result in early evaluation.

  • The evaluation usually begins with a review of dietary habits and symptoms. Your doctor may ask you to keep a diary of foods and beverages consumed for a specific time period.
  • If lactase deficiency is the suspected cause of gas, your doctor may suggest avoiding milk products for a period of time. A blood or breath test may be used to diagnose lactose intolerance.
  • Other breath tests may be obtained to determine if there is fructose malabsorption or overgrowth of intestinal bacteria.
  • Careful review of diet and the amount of gas passed may help relate specific foods to symptoms and determine the severity of the problem.
  • If a patient complains of bloating, the doctor may examine the abdomen for the sound of fluid movement to rule out ascites (build-up of fluid in the abdomen). The doctor also may do an exam for signs of inflammation to rule out diseases of the colon.
  • The possibility of colon cancer is usually tested in people 50 years of age and older. This possibility also is tested in those with a family history of colorectal cancer, especially if they have never had a colon examination (sigmoidoscopy or colonoscopy). These tests may also be appropriate for someone with unexplained weight loss, diarrhea, or blood not visible (occult blood) in the stool.
  • For those with chronic belching, the doctor will look for signs or causes of excessive air swallowing. If needed, an upper GI series (X-ray to view the esophagus, stomach, and small intestine) may be performed to rule out disease.

Last reviewed by a Cleveland Clinic medical professional on 10/25/2016.


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