Barium swallow

This is not a very common test but you may have a barium swallow if you are having difficulty swallowing solid food.

It helps the doctor investigate the area around the voice box (larynx) and the top of the food pipe (oesophagus).

It can help doctors stage mouth and oropharyngeal cancer.

About the test

You drink white barium liquid, which shows up on x-rays. Your doctor (radiologist) or radiographer then takes x-rays while you swallow the liquid. This test can show any growths or abnormal looking areas.

Preparing for your barium swallow

You can’t eat for 4 to 6 hours before the test. You might be able to drink water up to 2 hours before. The hospital gives you written instructions about this beforehand.

Talk to your doctor if not eating could be a problem for you, for example if you have diabetes.

Contact your hospital before your appointment if you are pregnant or think you might be.

What happens

You have a barium swallow as an outpatient in the radiology (x-ray) department. It takes 10 to 15 minutes.

A radiographer or an assistant takes you to a cubicle to change out of your clothes and put on a gown.

Once you’re in the x-ray room, you stand in front of the x-ray camera. You drink some white barium liquid. This is sometimes fruit flavoured but can taste chalky.  

Your radiologist or radiographer takes a series of x-rays as the barium passes down your throat and into your stomach. They might take some x-rays with you lying down.

After the barium swallow

Once the test is over you can get dressed and go home. You can eat and drink normally.

You pass the barium out of your body in your poo. So it will look pale or white for a few days.

Barium can cause constipation. To try to prevent this, you should drink plenty of water and eat more fibre for a few days after the test. Talk to your doctor, nurse or pharmacist if you haven’t been to the toilet for a few days.

Some people feel a bit sick after a barium swallow. This should get better as the barium passes through your system.

Possible risks

A barium swallow is a safe test. It helps doctors find out what may be causing your symptoms but, as with any medical procedure, there are possible risks. 

Your doctor makes sure the benefits of having the test outweigh the possible risks.

A small amount of barium liquid can go into the airway when you drink it. Physiotherapy can help you to cough it up but most people don’t need it. Tell your doctor or radiographer before the test if you have problems swallowing.

X-rays and radiation

Exposure to radiation from x-rays can slightly increase your risk of developing cancer in the future. The amount of radiation in medical tests is low. Talk to the doctor or radiographer if you’re worried about this.

Getting your results

You should get the results in 1 or 2 weeks. The doctor who arranged the barium swallow gives them to you.

Waiting for results can make you anxious. You can ask your doctor or nurse how long it takes to get the results. Contact the doctor who arranged the test if you haven’t heard anything after a couple of weeks.

You can also contact the Cancer Research UK nurses on freephone 0808 800 4040. The lines are open from 9am to 5pm, from Monday to Friday.
Last reviewed: 
01 Jun 2021
Next review due: 
01 Jun 2024
  • Head and Neck Cancer: United Kingdom National Multidisciplinary Guidelines
    V Paleri and N Roland
    The Journal of Laryngology & Otology, 2016, Volume 130, Supplement 2 

  • ACR-SPR Practice parameter for the performance of the modified barium swallow
    American College of Radiology, 2017

  • The Royal Marsden Manual of Clinical Nursing Procedures (10th edition)
    S Lister, J Hofland and H Grafton 
    Wiley Blackwell, 2020

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