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MRI Small Bowel Preparation (Klean Prep) – Patient Information

This page gives information to patients having a small bowel MRI. Magnetic Resonance Imaging (MRI) is a painless examination which uses powerful magnetic field without the use of radiation. This procedure takes approximately one and a half hours

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What is an MRI small bowel preparation?

MRI Enterography or small bowel, is a test which uses an MRI scanner to produce images of the small bowel as it is difficult to see it. The aim of the preparation for this is to drink enough liquid to fill the small bowel so we can see it better on the scan. Water doesn’t work very well, and so we use a preparation called Klean Prep.

When can I discuss the test?

You can discuss this with your referring doctor or with the radiographer before the procedure. On the day before your test, ingest a light diet only. Do not eat fruit or vegetables.

How do I prepare for my appointment?

You need to arrive one hour before your scan time to drink the MRI preparation. You will be advised of the time you need to arrive when you make the appointment.

If you have a morning appointment, do not eat food after midnight the night before, but please drink plenty of water. If you have an afternoon appointment, eat an early light breakfast, and have nothing to eat after this. (Preferably fast for 4-6 hours). You may still drink water.

How long will it take?

The scan takes approximately 30-40 minutes. However you need to arrive one hour before your appointment, so please be aware that this test can take up to two hours in total.

Asking for your consent

The radiographer will ask you if you are happy for the scan to go ahead (verbal consent) and may only involve the radiographer checking that you are booked for the correct scan. If you do not wish to have the scan or are undecided, please tell the radiographer. It is your decision and you can change your mind at any time. Please remember to ask the radiographer any questions you have at any time.

What happens once I have had the drink?

This drink is a mild laxative, and will help us see your small bowel clearly on the scan, as it distends the bowel with liquid. You may experience some diarrhoea as a result of this drink 1-3 hours after consuming the liquid. After taking the liquid you will be taken into the scan room where the process will be explained to you by the radiographer. Please refer to the Small Bowel MRI information sheet for a more detailed description of the test.

What happens after the test?
We will ask you to stay in the department for 15-20 minutes before going home. You may wish to use the toilet as the Klean Prep can cause diarrhoea. You should also keep this in mind when making your way home.

If you are diabetic please continue to take any medication as usual.

Before your MRI scan
You cannot have a MRI scan if you have any of the following:
• Cardiac pacemaker
• Cochlear (ear) implant
• A metal aneurysm clip in the brain
• Metallic fragments in the eye
• Certain mechanical implants

Are there any risks?

MRI small bowel is regarded as a very safe test. Very rarely, problems can occur, and if they do, they are similar to those which could happen with other methods of examining the bowel. These include:
• Abdominal discomfort
• Faint-like reactions
• Reaction to the injected contrast (dye)
• Diarrhoea

Your doctor has asked for this test because they feel that the benefits are greater than the risk of not having the examination. Even so, we cannot guarantee that this test will detect all abnormalities in the bowel.


• If you are taking medication please check with your referring consultant to see if you can carry on taking it
• If you are pregnant or have had difficulties in the past with Klean Prep please call us for advice on 0207 467 4317

How do I get my results?

We will send your results to the hospital consultant or GP who asked us to do the test.

Contact us

Please contact the Imaging team about any general concerns on 0207 467 4317. However, if you experience any symptoms of concern please contact your GP or go to your local Emergency Department (A&E).

Your comments and concerns

If you have any questions or concerns about your medicines, please speak to the staff caring for you. For support or advice please speak to your consultant or the Imaging department on 0207 467 4317.

Language and accessible support services

If you need an interpreter or information about your care in a different language or format, please get in touch.