Barium sulphate is a liquid, which is opaque to X-rays and, therefore, shows up on film.

Uses
It is used in enema form for highlighting diseases of the large bowel, e.g. Crohn's disease and ulcerative colitis. Sometimes it may also flow back into the terminal ileum to reveal diseases there.

Preparation
This involves cleaning all waste material from the bowel and following a special diet. Instructions must be followed carefully as poor preparation may spoil the results.

The day before examination a strong laxative solution is given. This is usually two sachets of Picolax - one sachet is taken at 8am and the second is taken 2-4 hours after lunch. To reduce the formation of faeces a special diet is taken:

Breakfast
Boiled egg, White toast, Black tea or coffee

Lunch
White meat / White fish
Boiled or mashed potatoes or rice, (No vegetables), (No fruit)
Fruit flavoured jelly / Plain yoghurt / Black tea or coffee / Fruit squash

Supper
Clear soup
Fruit flavoured jelly
Black tea or coffee
Fruit squash

NB It is most important that liberal amounts of fluid are taken during the day as Picolax can cause the frequent passage of watery motions, leading to dehydration. A glass of water should be taken every hour.

You will be asked to have nothing further to eat from midnight except your usual medication. You may continue to drink water only. If you have an afternoon appointment you can usually have the restricted breakfast as on the previous day.

The Examination
Barium, together with a little air to inflate the bowel, is administered through a tube inserted in the rectum. A small injection of a substance called buscopan is given to relax the bowel muscle. The barium is then allowed to drain and a small amount of air is blown into the bowel. This distends the gut and allows 'double contrast' film to be taken in which the lining of the gut, coated in barium, stands out clearly against the air inside the bowel. This enables the radiologist to see quite small lesions such as ulcers and polyps. In order to get better views during the examination, the radiologist will ask you to turn onto your back and side and he will tilt the x-ray table.

The radiologist will send a report to your doctor who will then prescribe the appropriate treatment or carry out further investigations.

After the Test
You will be given a laxative solution to help the barium pass more easily out of the bowel. You will find that the bowel motions will be white, due to barium, for the next few days. Try and get rid of as much barium as quickly as possible, as it sometimes leads to constipation.