Barium Enema

Medically Reviewed by Carmelita Swiner, MD on September 02, 2022
Written by WebMD Editorial Contributors
4 min read

A Barium enema is an examination of your lower gastrointestinal tract (your doctor may call it your lower GI tract) using X-rays. It’s also known as a colon X-ray.

X-rays show doctors what's happening inside your body. They produce helpful images of your bones, fat, muscle, and even the air in your lungs. But when it comes to your colon, X-rays aren't as clear. A barium enema helps get the best detail possible.

Barium is a white, chalky powder. A technician mixes it with water and passes it through a small tube in your rectum. This barium mixture covers the lining of your colon and lets your doctor take images of it at work, highlighting anything that may be causing trouble.

If you're having any of these issues, a barium enema can help your doctor narrow down the cause:

A barium enema can also help diagnose conditions from your rectum to your small intestine. These include:

 

Because X-rays of any kind may harm a baby in the womb, pregnant women usually don’t get them.

Though the amount of radiation you get is low, too much radiation from X-rays can cause cancer. But it takes years for this to happen, and the chance of getting cancer is small when compared to the benefit of how easily a barium enema can diagnose a problem.

In rare cases, barium enemas can cause complications like:

To get the best images, your colon needs to be completely empty. Anything left in it might be considered part of the problem.

Your doctor will give you specific instructions before the test. Follow them carefully. Make sure it's OK to take your regular medications and supplements.

Here's what you can expect:

  • A special diet. The day before the exam, you may be asked to steer clear of all solid food and drink clear liquids only, such as broth and tea.
  • Nothing after midnight. This is called fasting. Prepare to stop eating and drinking at midnight before the exam.
  • Take a laxative. The night before your exam, you may be asked to take a laxative in pill or liquid form to empty your colon.
  • Colon cleansing. Your doctor may suggest you use an enema kit, which has a solution that cleans all residue from your colon.

As is the case with other X-rays, you may be asked to take off any jewelry, metal objects, eyeglasses, and dental devices that could alter the images.

Usually, a barium enema is done as an outpatient procedure, which means you go in for the test and go back home the same day.

Since you aren’t able to eat or drink before the test, most doctors give barium enemas in the morning. The test can take anywhere from a half-hour to an hour.

Two people will guide you through the barium enema: the radiology technician and a radiologist, a doctor who's trained to perform and read the X-rays. Here's how it works:

  • You'll lie on your side on a table and have an X-ray to make sure your colon is completely clean.
  • The technician will guide an enema into your rectum. The enema bag holds the barium liquid. Near the tip of the tube is a balloon that keeps the barium inside your body.
  • As the barium flows into your colon, you may feel cramping or the urge to have a bowel movement. This can be uncomfortable. Try to breathe and relax so the tube stays in place. You don’t want the barium to leak out. If needed, you can get a bedpan or go to a bathroom.
  • They may pump air in to help the barium cover every part of your colon.
  • The radiologist may ask you to hold your breath and turn different ways so they can take images from various angles. The radiologist may also press on your stomach area to move your colon into a better position for X-rays.
  • Once the radiologist is finished, some of the barium will flow back through the tube into the bag. You can release the rest of the barium, and the air, in the restroom.

You may get a laxative or an enema to make sure all the barium is out of your body. You should be able to eat and drink normally afterward. You may have white bowel movements as the barium works its way out of your system.

Call your doctor if you feel constipated, don't have a bowel movement for 2 days after the exam, or are having a hard time passing gas from your rear end.

The radiologist will examine your images and send a report to your doctor. There are two kinds of results:

  • A positive result means the radiologist found something abnormal in your colon.
  • Anegative result means your colon is working normally.

If you have a positive result, expect to have more tests, like a colonoscopy, that will either look deeper into the issue, monitor it for change, biopsy an area, or remove a growth.