Barium enema

A barium enema is a test that involves passing a white liquid, called barium sulphate, into your bowel through your bottom.

Information written and reviewed by Certified Doctors.

Contents

Introduction

A barium enema is a test that involves passing a white liquid, called barium sulphate, into your bowel through your bottom. This liquid coats the inside of the bowel so that a clear X-ray image of this area can be taken.

It allows doctors to investigate problems such as:

When you may be referred for a barium enema

Your doctor may recommend that you have a barium enema if you have noticed blood in your stools or if you have an unexpected change to your bowel movements, such as diarrhoea or constipation.

If you have a family history of colorectal polyps or colorectal cancer and you have unexplained lower abdominal pain, a barium enema may be used to investigate the cause.

In some cases, a CT scan or a colonoscopy (a type of endoscopy) may be used instead of a barium enema.

A barium enema examination is not advisable if you are pregnant because you will be exposed to some radiation. The amount of radiation used during the procedure is considered safe for the patient but could be dangerous for an unborn child. Therefore, if you are pregnant or think you might be, you must inform your doctor or radiographer at the hospital before the examination. Read more about the risks of a barium enema.

How it is carried out

During a barium enema, liquid barium sulphate is passed into your bowel through a small soft tube inserted into your bottom. The liquid coats the inside of your bowel.

At the same time, air is usually pumped through the tube to expand the large bowel. This helps to make the images as clear as possible.

The whole process of injecting the fluid and taking the X-ray takes around 15 to 30 minutes. It should not be painful but can cause some discomfort and bloating, mainly due to the large bowel stretching when the air is pumped in.

The X-ray images are analysed by a radiologist after the appointment. A radiologist is a doctor specially trained to carry out examinations and interpret medical images, such as X-rays. A report is given to your doctor, usually within 14 days.

Read more about how a barium enema is performed.

Risks

Before going ahead with a barium enema, your doctor and radiologist will weigh up any risks of the procedure against the benefits of diagnosing a potentially serious disorder or disease, such as bowel cancer.

There are some risks to consider before having a barium enema, although they are generally rare and it is usually a safe procedure. A barium enema may not be used in certain groups of people, such as pregnant women or people who have been diagnosed with colitis (inflammation of the large bowel).

Radiation exposure

Exposure to radiation is low as the duration and level of radiation used is kept to a minimum. You will be exposed to X-rays for about two to three minutes. The quantity of radiation you are exposed to is equivalent to what you would receive naturally from the environment over about three years.

You should not have an X-ray if you are pregnant, as there is a slightly higher risk of an unborn baby being harmed by the radiation. A barium enema will only be used in very exceptional circumstances if you are pregnant.

Bowel perforation

There is a small risk of bowel perforation. A perforation is a small hole in the bowel. This is a serious complication that can be fatal. However, it is extremely rare and generally only happens if you have a problem such as severe inflammation of the large bowel.

Side effects

There is a risk of side effects from the drug Buscopan which is given to relax the muscles of your bowel wall. Your radiologist will check whether you have a history of heart disease or glaucoma before giving the injection to you. The drug can cause temporarily blurred vision.

Some people may not tolerate barium very well and it may give them an upset stomach or constipation. In much rarer cases, it may cause an allergic reaction.

How it is performed

A barium enema is a routine procedure. You will only be in hospital for about an hour and should be able to go straight home afterwards.

You can take a family member or friend with you, but they may not be allowed into the X-ray room. It is advisable that you bring someone with you to drive you home, as you may not be able to drive straight after the procedure.

Preparing for a barium enema

Before having a barium enema, your bowel should be empty of any stools to make sure clear pictures can be taken. Your doctor will advise you about the type of food you can eat the day before the test.

You will be prescribed a strong laxative to clear your bowel. Follow the instructions carefully and stay at home the day before your test to avoid any inconvenience and to be as comfortable as possible.

If you are diabetic and take insulin or tablets, make sure you eat enough on the day before your test so that your blood sugar levels do not drop. Your doctor and radiologist will give you special advice about what you can eat the day before your procedure.

The procedure

You will be shown to a private cubicle where you can undress and remove any jewellery. You will be asked to put on a gown before being shown into the X-ray room.

You will lie on an X-ray table on your side or front, and a small soft tube will be gently inserted a few centimetres into your bottom (rectum). You may also be given an injection, usually of Buscopan, a drug that helps relax the muscles of the wall of the colon. Many radiologists give this injection routinely at the start of each barium enema procedure, unless you have a history of heart disease or glaucoma.

The barium sulphate liquid is passed through the tube and into your colon, and the radiologist or radiographer will be able to see this on a television screen. You may be asked to lie in a number of different positions to help the flow of the barium liquid, and to get it to spread evenly along the wall of the colon. Air may also be pumped into the colon to expand it and push the barium sulphate liquid inside. This may feel a bit uncomfortable, like having trapped wind.

After the barium has been passed into the colon, a number of X-ray pictures will be taken from various positions. You may be asked to stand up and lie down. As the X-rays are being taken, you will be asked to hold your breath.

The test usually takes about 15 to 30 minutes and is not painful, although you may feel a little discomfort. When the X-rays have been taken, the tube will be removed and you can then go to the toilet.

The test results will be sent to your doctor within 14 days.

Does it hurt?

Having a barium enema should not hurt but may cause some discomfort. Some people experience cramp-like pain during and a short while after the procedure.

Some people also worry that they may not be able to hold the barium liquid and air in their bowel. Try to hold on to it by keeping the muscles of your bottom very tight, because if you let go too soon it may affect the X-ray images.

Some people leak barium fluid onto the X-ray table, but try not to worry too much about this happening.

Afterwards

You can normally eat straight away after the procedure, but it is a good idea to drink plenty of fluids for three days afterwards to avoid constipation. After the procedure:

  • You will need to go to the toilet. It's a good idea to stay close to a toilet for the next few hours.
  • Your stools will appear white and discoloured for a few days. This is the barium liquid passing out of your system.
  • If you have a Buscopan injection, you will need to wait up to an hour before you drive as it can blur your vision. It is best to take someone with you to drive you home.
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