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Pelvic floor and bowel tests

Defecating proctogram: what the test shows and what to expect

A defecating proctogram, also spelled defaecating and sometimes called evacuation proctography, is a moving X-ray test that shows how the rectum and pelvic floor muscles work when you try to empty your bowels. It is used to help explain symptoms such as difficulty passing stool or incontinence. This guide explains how it is done, how to prepare, what it can feel like and what happens afterwards.

Last checked: 2026-10-10

Key facts

At a glance.

  • What it looks at

    Northern Care Alliance describes it as an examination of the rectum (back passage) to see how it works when you try to empty your bowels, and how the muscles work when you try to go to the toilet.

  • No physical preparation

    Rotherham NHS Foundation Trust says there is no physical preparation, you may eat and drink normally and take prescribed medicines, although some patients are asked to drink barium liquid first.

  • Short test

    Northern Care Alliance says the examination generally takes around 20 minutes, but occasionally longer. Rotherham says to allow about half an hour, or an hour and a half if a barium drink is needed.

  • Uses X-rays

    It involves a small dose of radiation, so staff ask whether you could be pregnant. Rotherham says it must only take place during the first 10 days of the menstrual cycle.

  • MRI alternative

    Cambridge University Hospitals describes an MRI defecating proctogram that uses no radiation or X-rays, which some centres offer instead.

What a defecating proctogram is

Most bowel tests look at the structure of the bowel. A proctogram looks at its movement and function. Northern Care Alliance explains that it is an investigation of the rectum to see how the muscles work when you try to go to the toilet, and that it may help to explain some of your symptoms.

Rotherham NHS Foundation Trust says it can help to find a diagnosis if you have anal or rectal symptoms, and shows whether you have any weakness of the muscles in the pelvic area. It may be performed as part of a series of other tests, according to the Northern Care Alliance leaflet.

Why you might be offered it

It is requested by a specialist when symptoms such as difficulty emptying the bowel, or incontinence, are not explained by simpler tests. The NHS says people with constipation who are not improving with treatment should see a GP, and recurring problems with emptying can then lead to specialist referral.

Rotherham lists endoanal ultrasound as another test that looks at the anatomy of the sphincter, and notes that MR proctography is offered at a few centres as an alternative. Your referring clinician will discuss which suits you.

Preparing for the test

Rotherham says there is no physical preparation and you may eat and drink normally and take prescribed medicines. It adds that if you also have a colonoscopy or sigmoidoscopy booked within 7 days before or after, the proctogram should be rearranged.

Some patients need to drink a barium liquid before the procedure. In that case you are asked to attend 1 hour before the appointment, because the liquid takes about an hour to reach the small bowel, where it helps the team see the small bowel. Allow time accordingly.

If there is any chance you could be pregnant, tell the department beforehand. Northern Care Alliance says all persons of childbearing age will be asked this when X-rays are to be used. Rotherham says the examination cannot take place if you are pregnant and must only take place during the first 10 days of the menstrual cycle, counting day 1 as the first day of your period.

What happens during the examination

You change into a gown, and a healthcare professional explains the procedure and checks for allergies. It is carried out by a specially trained radiographer or a radiologist, with a nurse present, according to Rotherham.

You lie on your left side. Northern Care Alliance says a digital rectal examination is performed and a small tube is inserted into the rectum, through which barium paste is put in, and the tube is removed. You are then asked to sit on a portable toilet next to the X-ray machine and, when comfortable, to try to pass the barium into it while X-ray images are recorded. A screen is used for your privacy.

Rotherham notes that the barium paste is only licensed for oral use but has been deemed safe for rectal administration, and that this is explained when you attend. After the test you are shown to a private toilet next to the X-ray room.

What it feels like

Northern Care Alliance says the examination may be a little uncomfortable but should not be painful. Rotherham says there should be very little or no discomfort and no unpleasant after effects. It is, however, an embarrassing test for many people. The Northern Care Alliance leaflet acknowledges that you may find it embarrassing but says it is a very routine examination and staff will do everything to put you at ease.

If you find you cannot pass the paste, tell the team and carry on with their guidance.

Risks, aftercare and results

Northern Care Alliance describes the test as safe, with possible risks including a little bleeding from the back passage, which generally stops without action, and barium staying in the rectum for a few days and making your stools look pale and chalky. If some barium is still in the rectum, you may be given a glycerine suppository to take home to prevent constipation.

Rotherham says you may follow your normal diet but should increase your fluid intake for the rest of the day, and that you may notice white barium in your faeces for a few days, which is normal. Results go to the doctor who referred you, who will discuss them by phone, letter or at your next appointment.

Frequently asked

Questions people ask.

Quick, plain-English answers to the questions we hear most.

  • What is a defecating proctogram?

    Northern Care Alliance describes it as an examination of the rectum that shows how it works when you try to empty your bowels, using X-rays and barium paste.

  • Do I need to fast or take laxatives?

    Rotherham says there is no physical preparation and you may eat and drink normally. Some people drink barium liquid first. Follow the instructions in your appointment letter.

  • Is it painful?

    Northern Care Alliance says it may be a little uncomfortable but should not be painful. Rotherham says there should be very little or no discomfort.

  • How long does it take?

    About 15 to 20 minutes for the examination itself, according to Rotherham and Northern Care Alliance, with extra time before and afterwards. A barium drink makes the visit longer.

  • Is the radiation dose safe?

    Northern Care Alliance says modern equipment keeps the dose as low as possible, and your doctor will have decided that the benefit outweighs the very small risk.

  • Can I have it if I might be pregnant?

    Tell the department beforehand. Rotherham says the test cannot take place if you are pregnant and should only be done in the first 10 days of the menstrual cycle.

  • What if I cannot pass the barium?

    Tell the staff and follow their guidance. They will use the images they have been able to record.

  • Will my stools look different afterwards?

    Yes. Both leaflets mention white or pale chalky stools for a few days as the barium clears, which is normal.

  • Is there an alternative without radiation?

    Cambridge University Hospitals describes an MRI defecating proctogram using gel and no X-rays. Availability varies between hospitals.

Where this comes from

Sources and checking.

This guide is for information, not medical advice.

Your GP or consultant knows your history and can tell you which parts apply to you. If your symptoms are severe, rapidly worsening, or come with red-flag features, seek urgent medical care. Figures and availability change, so treat them as a guide and confirm with the provider.

Published 2026-10-10, next review 2027-10-10.

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