Barium enema

A barium enema is an X-ray exam that can detect changes or abnormalities in the large intestine (colon). The procedure is also called a colon X-ray. An enema is the injection of a liquid into your rectum through a small tube. In this case, the liquid contains a metallic substance (barium) that coats the lining of the colon. Normally, an X-ray produces a poor image of soft tissues, but the barium coating results in a relatively clear silhouette of the colon.

In the past, doctors used barium enema to investigate the cause of abdominal symptoms. But this test has mostly been replaced by newer imaging tests that are more accurate, such as CT scans. In the past, your doctor may have recommended a barium enema to determine the cause of signs and symptoms, such as the following: Abdominal pain Rectal bleeding Changes in bowel habits Unexplained weight loss Chronic diarrhea Persistent constipation Similarly, a barium enema X-ray previously may have been ordered by your doctor to detect such conditions as: Abnormal growths (polyps) as part of colorectal cancer screening Inflammatory bowel disease

A barium enema exam poses few risks. Rarely, complications of a barium enema exam may include: Inflammation in tissues surrounding the colon Obstruction in the gastrointestinal tract Tear in the colon wall Allergic reaction to barium Barium enema exams generally aren't done during pregnancy because X-rays present a risk to the developing fetus.

Before a barium enema exam, you'll be instructed to empty your colon. Any residue in your colon may obscure the X-ray images or be mistaken for an abnormality. To empty your colon, you may be asked to: Follow a special diet the day before the exam. You may be asked not to eat and to drink only clear liquids — such as water, tea or coffee without milk or cream, broth, and clear carbonated beverages. Fast after midnight. Usually, you'll be asked not to drink or eat anything after midnight before the exam. Take a laxative the night before the exam. A laxative, in a pill or liquid form, will help empty your colon. Use an enema kit. In some cases, you may need to use an over-the-counter enema kit — either the night before the exam or a few hours before the exam — that provides a cleansing solution to remove any residue in your colon. Ask your doctor about your medications. At least a week before your exam, talk with your doctor about the medications you normally take. He or she may ask you to stop taking them days or hours before the exam.