Both a barium swallow and a barium meal test involve you swallowing a liquid suspension of barium sulphate before a series of X-rays are taken of your upper digestive tract. In a barium swallow test, X-ray images are taken of your pharynx (throat) and your oesophagus (the passageway that connects your throat to your stomach; sometimes called your gullet).
In a barium meal test, X-ray images are taken of your stomach and the beginning of your duodenum (the beginning of your small intestine, the passageway that takes food away from your stomach). A barium meal test is often performed straight after a barium swallow test.
Barium is a naturally occurring element that appears white on X-ray. In these tests, the barium is given as a cup of flavoured drink — like a milkshake. When swallowed, barium coats the walls of the digestive tract, which allows the shape of your upper digestive tract to be outlined on an X-ray. Without the barium your upper digestive tract would be barely visible on X-ray.
A barium swallow test may be suggested if you are having difficulty swallowing, or if you have chest pain or reflux (backflow of stomach juices into the lower part of the oesophagus).
A barium meal test may also be suggested if you are having these problems, or if you are having unexplained vomiting, pain in your abdomen, severe indigestion or blood in your stool (which may be coming from your stomach or duodenum or elsewhere in your digestive system).
Barium swallow and barium meal tests help doctors to diagnose inflammation, ulcers or tumours in the oesophagus, stomach or duodenum.
So that your upper digestive tract is empty for the test, you will be advised to have no food or drink for several hours before the test. Often this means no food or drink from midnight on the day before a morning test. (Fasting instructions may vary slightly among X-ray centres, so remember to follow exactly the particular instructions that you are given.) If you have diabetes, contact the centre performing the test, or your doctor, about how to prepare for the test.
You may be asked not to smoke for several hours before the test, as smoking causes extra secretions to flow into your digestive tract.
Your doctor will usually advise you not to take your regular oral medicines on the day of the test, until after the test is finished. However, check with your doctor whether this applies to all your regular medicines. It is especially important not to take antacids before the test.
The images produced during a barium swallow and meal test are either moving X-ray images or still X-ray images. Moving images are viewed by a radiologist on a screen and are useful for observing digestive functions such as swallowing and fluid outflow from the stomach. Still images are viewed by a radiologist on an X-ray film and are useful for detecting abnormalities in the wall of the digestive tract such as ulcers or tumours.
You will usually go to a radiology or imaging centre, or sometimes to the radiology department of a hospital, to have the barium swallow or barium meal test performed. You will be asked to change from your clothes into a simple gown so that folds of clothing and metal fasteners, for example, do not interfere with producing clear X-ray images.
In the X-ray room you will be told when and how fast to drink the barium solution, usually about one cup in total. If X-rays are to be taken of your stomach (a barium meal test), you may also be asked to drink a small amount of one or 2 other liquids. These liquids combine to produce a gas that expands your stomach, making it easier to detect any abnormalities in its lining. This can make you feel a little ‘gassy’, but you will be asked to resist the urge to burp so that the gas remains in your stomach until after the X-rays have been taken. Doctors call this type of barium meal a ‘double contrast study’.
Sometimes you may also be given an injection of a muscle relaxing medicine to slow the natural movement of the digestive tract. This helps to produce clear X-ray images. If you have glaucoma, you must tell the staff before the test, as a different injection will need to be used.
The first X-rays will be taken while you are standing, usually against a flat panel, with X-ray equipment opposite. As you swallow, the radiologist will watch on a screen moving images of the barium passing from your throat and down your oesophagus. Still X-rays will also be taken to show the barium outlining your digestive tract — you will be asked to hold your breath for a short time when these still X-rays are taken to ensure that clear images are obtained.
After the standing pictures are taken, you will be asked to lie on a table while further X-rays are taken of your oesophagus, stomach and small intestine. You will be asked to roll to various positions on the table so that the barium coats all areas of the upper digestive tract wall. Again you will be asked to remain still and hold your breath for short periods while still X-rays are taken.
A barium swallow and/or meal test is likely to be finished within 30 minutes. The images are checked and only if some images are blurred or further angles are required will additional X-rays be taken.
Occasionally, your doctor may require additional ‘follow through’ X-rays to track the movement of the barium through the small bowel. This may take between one and 4 hours, depending on how quickly the fluid moves through your digestive tract.
After the X-rays have been taken and checked to make sure they are clear, a radiologist will view the images in detail and will write a report of their findings for your doctor. You will need to make a follow-up appointment with your doctor to discuss the test results.
After the test you can resume eating normal food. Barium is likely to cause constipation, so you should eat high-fibre foods such as fruit and vegetables and drink plenty of liquids. Your stools will be a whitish colour for 2 or 3 days after consuming the barium. If you experience problems with constipation in the days following the barium test, contact your doctor.
These are safe tests, with a relatively low level of radiation exposure. However, a barium swallow or meal test is not suitable for pregnant women or people with some conditions of the digestive tract, including suspected perforation (a hole in the gut wall) or obstruction (blockage).
Some people experience temporary stomach upset, headache or dizziness after a barium meal or swallow. More serious reactions to the barium are possible but rare — contact your doctor if you experience any symptoms that are unusual for you after a barium meal or swallow.
If a muscle relaxant is used it can cause blurred vision for a short time so you may not be able to drive home straight away.
Last Reviewed: 25 November 2009