DIGESTIVE DISEASE CENTER | Gastroenterology home | Surgery home

Patient care — diagnostic tools, tests, procedures

Barium enema: An X-ray examination of the large intestines, pictures are taken after rectal instillation of barium sulfate (a radiopaque - contrast medium).

Alternative Names: Lower GI, lower gastrointestinal series

How the test is performed: This test may be done in an office or a hospital radiology department. You lie on the X-ray table and a preliminary X-ray is taken. You are asked to lie on the side while a well lubricated enema tube is inserted gently into your rectum. The barium, a radiopaque (shows up on X-ray) contrast medium, is then allowed to flow into the colon. A small balloon at the tip of the enema tube may be inflated to help keep the barium inside. The flow of the barium is monitored by the health care provider on an X-ray fluoroscope screen (like a TV monitor). Air may be puffed into the colon to distend it and provide better images.

Barium enema
A barium enema is performed to examine the walls of the colon. During the procedure, a well lubricated enema tube is inserted gently into the rectum. The barium, a radiopaque (shows up on X-ray) contrast medium, is then allowed to flow into the colon. The flow of the barium is monitored by the health care provider on an X-ray fluoroscope screen (like a TV monitor). The test is used to detect colon cancer. The barium enema may also be used to diagnose and evaluate the extent of inflammatory bowel diseases.


You are asked to move to different positions and the table is slightly tipped to get different views. At certain times when the X-ray pictures are taken, you hold your breath and be still for a few seconds.

The enema tube is removed after the pictures are taken and you are given a bedpan or helped to the toilet. You then expel as much of the barium as possible. One or two X-rays may be taken after the barium is expelled.

If a double or air-contrast examination is being done, the enema tube will be reinserted gently and a small amount of air will be gently introduced into the colon, and more X-ray pictures are taken. This gives a more detailed picture. The enema tube is then removed, and you again empty the colon.

How to prepare for the test: Thorough cleaning of the large intestine is necessary for accurate pictures. Test preparations include a clear liquid diet, drinking a bottle of magnesium citrate (a laxative), and warm water enemas to clear out any stool particles.

How the test will feel: There is a feeling of fullness during the procedure, moderate to severe cramping, the urge to defecate, and a general discomfort. The X-rays themselves are painless.

Why the test is performed: The test is used to detect colon cancer. The barium enema may also be used to diagnose and evaluate the extent of inflammatory bowel diseases.

Normal Values: Barium should fill the colon uniformly and show normal bowel contour, patency (should be freely open), and position.

What abnormal results mean: Abnormal findings may include cancer, diverticulitis (small pouches formed on the colon wall that can become inflamed), polyps (a tumor, usually noncancerous, that grows on the mucous membrane), inflammation of the inner lining of the intestine (ulcerative colitis), and irritable colon. An acute appendicitis or twisted loop of the bowel may also be seen.

Additional conditions under which the test may be performed:

  • annular pancreas
  • CMV gastroenteritis/colitis
  • colorectal polyps
  • Crohn's disease (regional enteritis)
  • Hirschsprung's disease
  • intestinal obstruction
  • intussusception (children)
  • pyloric stenosis

What the risks are: There is low radiation exposure. X-rays are monitored and regulated to provide the minimum amount of radiation exposure needed to produce the image. Most experts feel that the risk is low compared with the benefits. Pregnant women and children are more sensitive to the risks of the X-ray.

A more serious risk is a perforated colon, which is very rare.

Special considerations: CT scans and ultrasounds are now the tests of choice for the initial evaluation of abdominal masses.

Return to Patient info page