Barium tests are used to help see the outline of the upper parts of the gut (gastrointestinal tract) such as the gullet (oesophagus), stomach and upper gut (small intestines).
Note: the information below is a general guide only. The arrangements, and the way tests are performed, may vary between different hospitals. Always follow the instructions given by your doctor or local hospital.
Why is barium used during some X-ray tests?
The gut (gastrointestinal tract) does not show up very well on ordinary X-ray pictures. However, if you drink a white liquid that contains a chemical called barium sulphate, the outline of the upper parts of the gut (oesophagus, stomach and small intestines) shows up clearly on X-ray pictures. This is because X-rays do not pass through barium.
Types of barium test
Depending on what part of your gut is being looked at, you may have one or more of the tests listed below. In each test, the barium coats the lining of the gut being tested. Therefore, abnormalities in the lining or structure of the gut can be seen on the X-ray pictures.
In each of the following tests, several X-ray pictures are taken using low-dose X-rays. The total amount of radiation for each test is quite small and thought to be safe. The X-ray machine is usually linked to a TV monitor. Still pictures, or a video recording of X-ray pictures taken in quick succession, can be taken if necessary.
In this test you drink some barium liquid. The barium liquid is often fruit-flavoured so it is pleasant to drink. You stand in front of an X-ray machine whilst X-ray pictures are taken as you swallow. This test aims to look for problems in the gullet (oesophagus). These include a narrowing (stricture), hiatus hernias, tumours, reflux from the stomach, disorders of swallowing, etc. You will usually be asked not to eat or drink for a few hours before this test. A barium swallow test takes about 10 minutes.
This is similar to a barium swallow (above) but aims to look for problems in the stomach and duodenum such as ulcers, polyps, tumours, etc. You drink some barium liquid, but you then lie on a couch whilst X-ray pictures are taken over your abdomen. It may take a little longer to do than a barium swallow.
So that the barium coats all around the lining of the stomach, the doctor doing the test (radiologist) may do one or more of the following:
Ask you to swallow some bicarbonate powder and citric acid before swallowing the barium. These 'fizz up' when they mix in the stomach and make some gas. (You may have to resist the urge to burp.) The gas expands the stomach and duodenum and also pushes the barium to coat the lining of the stomach and duodenum. This makes the X-ray pictures much clearer. It is the shape and contours of the lining of the stomach and duodenum which need to be seen most clearly on the pictures.
Ask you to turn over on to your stomach on the couch. Various X-ray pictures may be taken whilst you are in different positions.
Give you an injection of a drug that makes the muscles in the stomach and gut relax.
You will usually be asked not to eat anything for several hours before this test. (Food particles in the gut can make it difficult to interpret the X-rays.) However, you may be allowed sips of water up to two hours before the test.
Barium follow through
This test is similar to a barium meal but aims to look for problems in the small intestine. Therefore, you drink the barium liquid but then need to wait 10-15 minutes before any X-rays are taken. This allows time for the barium to reach the small intestine. You may then have an X-ray every 30 minutes or so until the barium is seen to have gone through all the small intestine and reached the large intestine (colon).
Small intestine enema
This test is similar to a barium follow through. However, instead of drinking the barium liquid, a thin tube is passed down your gullet (oesophagus), through the stomach and into the first part of the small intestine. Barium liquid is then poured down the tube. This test is not commonly done, but can give some different information about the small intestine to the tests above.
This is a test to take X-ray pictures of the colon. See separate leaflet called Barium Enema.
What preparation do I need to do?
This will depend on which of the tests listed above you need to have. Your local hospital will give you advice on what to do before the procedure.
After you have had a barium X-ray test
- You should be able to go home as soon as the test is finished.
- Some people feel a little sickly for a few hours afterwards.
- You can eat normally straight after any barium test.
- The barium may make you constipated. Therefore, to help prevent constipation:
- Have lots to drink for a day or so to flush the barium out of your gut.
- Eat plenty of fruit for a day or so.
- See your doctor if you haven't passed any poo (faeces) after three or four days.
- The barium will make your poo white or pale until it has all come out of your gut (after a day or so).
- If you had an injection to relax the muscles in your stomach, it may cause some blurring of your vision for an hour or so. If this happens it is best not to drive.
- The barium does not get absorbed into the body. Therefore, it is rare for a barium test to cause any other complications or side-effects.
Some other points about barium X-ray tests
- Tell your doctor if you have insulin-dependent diabetes, so that you can arrange for the best time for you to stop eating and for the test to be done.
- Pregnant women, if possible, should not have an X-ray test, as there is a small risk that X-rays may harm the unborn child. This is why women are asked before having an X-ray if they are, or might be, pregnant.
- Barium X-ray tests are done less commonly these days. The more common test to look into the oesophagus, stomach and duodenum is with a flexible telescope (endoscopy). However, there is still a place for barium tests to help assess various problems of the gut.
Dr Rachel Hoad-Robson
Dr Euan Lawson
Dr Hayley Willacy