What is a barium enema?
A barium enema is a special X-ray examination of the large bowel that uses a contrast medium to make the structure of the bowel visible on images. The aim is to get a clearer picture of changes such as narrowings, pouches, inflammation, or tumours in the large bowel.
How does a barium enema work?
Before a barium enema, the large bowel needs to be as clean as possible so that the lining can be seen clearly on the X-ray images. For this reason, a laxative is usually prescribed to be taken the day before the examination. Sometimes it is also recommended to eat only liquid foods the day before. On the day of the examination itself, the procedure usually takes place whilst lying on an examination table.
What makes this method special is the contrast medium, which is introduced into the large bowel through a thin tube inserted into the back passage. This is usually a whitish, thick liquid based on barium. It spreads throughout the entire large bowel and makes the bowel walls particularly easy to see on the X-ray images. During the examination, several X-ray pictures are taken from different angles. Sometimes air is also introduced into the bowel to show the folds of the lining more clearly.
After the examination is finished, the contrast medium is passed out of the body. Stools may look lighter in colour over the following days, but this is harmless and goes away on its own.
When is a barium enema used?
A barium enema is mainly used when other examination methods, such as a bowel scope (colonoscopy), are not possible or do not give enough information. Typical reasons for a barium enema include unexplained tummy pain, long-lasting diarrhoea, blood in the stool, suspected narrowings (stenoses), diverticula (pouches), polyps, or tumours. After bowel surgery, or in cases of inflammatory bowel conditions such as Crohn's disease or ulcerative colitis, a barium enema can also help to check on recovery or rule out complications.
Sometimes the method is also used when a colonoscopy could not be completed fully, for example because the bowel is very curved or a narrowing is blocking access.
What does it feel like during the examination?
Many people wonder whether a barium enema is painful or causes unpleasant side effects. Whilst the introduction of the contrast medium and air can cause a certain feeling of pressure or mild fullness in the tummy, most people report that the examination is quite manageable. Some find the introduction of air unusual, and it can lead to wind or a temporary urge to open the bowels. Strong pain does not usually occur.
After the examination, the tummy may still feel a little bloated or there may be a mild urge to use the toilet. These feelings usually pass quickly.
Are there any risks or side effects?
Like any X-ray examination, a barium enema does involve a certain amount of radiation exposure, but this is generally considered to be low. The contrast medium used is well tolerated and does not enter the bloodstream. Allergic reactions are extremely rare.
In very rare cases, injury to the bowel wall can occur, for example if it is already damaged or severely inflamed. The overall risk of this is low, and the examination is considered safe. Anyone who suffers from chronic inflammatory bowel conditions or has had recent bowel surgery should discuss the procedure carefully with their treating doctor.
How should you prepare?
Good preparation is essential so that a barium enema produces clear and useful images. The most important steps are taking a laxative the day before, avoiding solid food, and following the doctor's instructions for preparation carefully. Anyone who takes regular medicines should check with their doctor beforehand, as some may need to be adjusted.
No special aftercare is needed following the examination. It is a good idea to drink plenty of fluids so that the contrast medium is passed out of the body more quickly.
Alternative examinations for comparison
In recent years, the classic barium enema has become less commonly used, because a bowel scope (colonoscopy) usually provides more detailed information and tissue samples can be taken at the same time. Imaging methods such as computed tomography (CT) or magnetic resonance imaging (MRI) are also sometimes used, especially when particular questions need to be answered or a colonoscopy is not possible.
Nevertheless, the barium enema remains a valuable examination method in some situations, particularly when other procedures cannot be carried out or do not provide enough information.
What does the result of a barium enema show?
The X-ray images are assessed by a radiologist. They look for anything unusual, such as narrowings, pouches, changes to the bowel lining, or unusual movements of the bowel. Depending on what is found, further examinations or targeted treatments may be needed.
A barium enema is therefore an important tool for identifying or ruling out conditions of the large bowel, especially when other methods reach their limits.
