COVID-19 information for patients and families

To help protect our people, patients and communities, we are screening everyone who enters our main hospital buildings. Some of our entrances may be closed or have reduced access.

Please check our COVID-19 information page for more updates before coming to our sites.

Medical Imaging

X-ray > Exams & Procedures > Barium Enema

The barium enema is used to image the colon (large bowel). This examination uses contrast media (barium) to outline a structure that would otherwise be invisible on an X-ray.


The barium enema requires some preparation on your part. The preparation is designed to make the lining of the bowel clean and dry. This is to allow for uniform coating of the bowel wall.

The preparation can be uncomfortable at times, but is necessary for a successful examination.


The contrast used during a barium enema examination is barium. This is an element from the periodic table that is suspended in water. It has a high atomic number that makes it difficult for X-rays to pass through.

Most barium enemas done today also use air. After introducing the barium, air is used to fill the colon, so that a thin layer of barium is coating the bowel wall.

Barium is an inert substance. This means that is enters and exits the body in a same form. It does not interact with nor is it metabolized by the body, making it a very safe and effective contrast media.

About the Procedure

The procedure takes about 30 to 40 minutes.

When you arrive the day of your examination you will be escorted to an area where you can change your clothes. You will then be taken into the examination room where the procedure will take place. During the examination there will be two other people present: a technologist and a radiologist. The technologist will ensure your comfort and safety throughout the procedure and make sure that the equipment functions properly. The radiologist carries out the fluoroscopy. Fluoroscopy uses radiation just like conventional X-rays, but it is similar to a movie rather than a snap shot.

St. Michael's Hospital is a teaching facility and there may be a student technologist or radiology resident present for your examination. These students are highly trained and closely supervised to provide you with the best care while maximizing their education.

A small flexible tube will be placed in the rectum. It is through this tube that the barium and air will be introduced. The barium will be instilled first. You can expect to feel it but it is not painful or uncomfortable.

After barium is introduced, the bowel will be insufflated with air. This part of the procedure can cause some mild abdominal cramping. This is normal and your technologist will be with you to help you through it. Many patients report no discomfort at all during this procedure.

At this point, the radiologist will be ready to take specific images of the bowel. This requires quite a bit of movement on your part, and again the technologist will be there to assist you. When the radiologist is satisfied with the acquired images, the procedure will be over. Any excess barium will be drained out, the tube removed, and you will be taken to a private washroom.

You may be asked to return for one more picture. Otherwise, your procedure is over. You may change your clothing and go back to your regular activities. You may eat and drink normally at this time.

We ask that you drink eight to ten glasses of water a day for the two days following your procedure to help clear the barium out of your bowel, as it can lead to constipation.

The radiologist has only had a preliminary look at the images. They will need more time to examine the images before a diagnosis can be made, and the report sent to your doctor.