Colonic Transit Study

Your doctor has requested that you have a colonic transit study. We hope the following information will answer some of the questions you may have about this procedure.

What is a colonic transit study?

It is an examination that evaluates the function of your large bowel (or colon). This study assesses how quickly material moves through your bowel. The procedure is carried out by a specialist radiographer.

How do I prepare for a colonic transit study?

You may continue to eat and drink normally throughout the duration of this study. Do not use any laxatives before or during this study.

You will be given a pack of capsules which you will need to take over a period of 3 days and then you will come for your x-ray on the 6th day. Please take the capsules as near to 9:00am as possible on each day.

  • Day 1: Swallow the 2 capsules number one (1) on the foil
  • Day 2: Swallow the 2 capsules numbered two (2) on the foil
  • Day 3: Swallow the 2 capsules numbered three (3) on the foil
  • Day 4: There are no capsules to take today
  • Day 5: There are no capsules to take today
  • Day 6: Attend the Imaging Department, Gate 18, Southmead Hospital.

If you are vegetarian/vegan please be aware that the capsules contain gelatine.

You can continue to take your normal medication unless otherwise instructed; however please inform us if you are allergic to anything.

The procedure uses x-rays and the amount of radiation used is small, however if you think you may be pregnant please inform the imaging department before attending the appointment (NRPB 2014).

On the day of the procedure:

  • You will arrive at Gate 18 -whereby a member of the Imaging team will take you through to the fluoroscopy waiting room.
  • You will be asked to confirm your details and that you have taken the capsules. You will then be brought through to the x-ray room
  • You will be asked to lie down on the x-ray table and the radiographer will take an x-ray of your abdomen.

After the examination:

Once the radiographer has checked that the x-ray image is adequate, you may go home.

What are the risks associated with a colonic transit study?

There are no side effects from these capsules and they will be passed with your stool over the next few days if they haven’t done so already. 

How will I get the results?

You will not get an indication of the result at the time of the examination, as analysis of the images will take place after you have left the department.

The radiographer will review your examination at the earliest opportunity and compile a written report this will be sent to the doctor who requested the examination. Allow 7-10 days for the doctor to receive the report.

Finally we hope this information is helpful. If you have any questions either before or after the procedure the staff in the x-ray department will be happy to answer them.

The telephone number for the x-ray department can be found on the appointment letter.

References / Other resources:

Public Health England (2014) “Guidance – Exposure to ionising radiation from medical imaging: safety advice”

Oxford Radcliffe Hospitals NHS Trust (2012) “Transit study examination – Information for patients”

How to contact us:

Brunel building
Southmead Hospital
BS10 5NB

0300 555 0103

If you or the individual you are caring for need support reading this leaflet please ask a member of staff for advice.

© North Bristol NHS Trust. This edition published June 2021. Review due June 2023. NBT003311.

Colonic Transit Study