This leaflet answers common questions about how to prepare your bowel for radiotherapy. If you would like further information, or have any particular worries, please do not hesitate to ask your radiographer or doctor.

In all cases, a doctor will explain the bowel preparation before radiotherapy to you and answer any questions you may have. In most cases it will be possible for a friend or relative to accompany you for all or part of the procedure. Please ask your nurse or doctor.

Why is bowel preparation important?

Following your bowel preparation schedule before your radiotherapy treatment each day can help us make sure:

  • your treatment is accurate/given to the right area
  • your side-effects are kept to a minimum

If your bottom is full when you have your radiotherapy treatment, the rectum will bulge into the treatment area. This will cause your side-effects to be worse.

What do I need to prepare my bowel before radiotherapy?

The following are the different types of bowel preparation you may be asked to undergo, these will be explained to you. The radiographers will check the box of each type of preparation which is relevant to you. Please follow the instructions of your specific preparation before each appointment in the radiotherapy department.

An example of a bladder and bowel preparation schedule is shown in the table below. You will be given your own individual schedule which you should follow prior to your radiotherapy appointment.

Appointment day

  • Using your schedule, ensure your bowels are empty by: 10.45am
  • Empty your bladder: 10.45am
  • Drink 500ml of water over 10- 15 minutes: 11am
  • Stop drinking at: 11:15am
  • Scan time appointment: 12noon.

How is a bowel preparation using a microenema done?

Following your consultation where you are referred for radiotherapy, a prescription for microenemas will be organised for you. The radiographer will ask you if you have an inflammatory bowel disease, such as Crohn’s, or are allergic to any of the following ingredients that can be found in most fruits, jams and toothpaste: :

  • sodium citrate.
  • sodium lauryl sulphate.
  • sorbitol.

Your radiographer will explain how to use the microenemas and you should follow the below steps when completing preparations at home and before your appointment:

  • Take an enema tube from the packet and go into the toilet.
  • Pull or twist the cap off the end of the nozzle.
  • Squeeze a drop of liquid from the tube onto your finger and smear over the nozzle, this will help to avoid hurting your back passage.
  • Gently push the full length of the nozzle into your back passage (bottom).
  • Gently squeeze the tube until it is empty.
  • It is very important to keep squeezing the tube as you pull the nozzle out, this is to stop the medicine being drawn back into the tube.
  • Throw the empty tube into the bin and wash your hands.
  • Your enema can take from 15-45 minutes to work. Wait somewhere that you feel comfortable.
  • Do not drink any fluids after using the enema.
  • Go back into the toilet and try to empty your bowels. You will usually feel a sense of urgency when the enema has taken effect. Please don’t strain and don’t worry if you cannot empty your bowels or if only wind is passed – it may be that your bowel is already empty.
  • Empty your bladder at the same time as you empty your bowels.

If you have not emptied your bowel after 45 minutes, ask the reception staff to contact a radiographer if you are in the department. If you are at home and need to empty your bowel after the 45 minute window, try not to pass urine at the same time. If you do empty your bladder, you should start to drink another 500mls of water.

We ask that you practice using the microenema at home the day before your radiotherapy planning CT scan appointment so that you are confident in their use.

If you have any concerns or queries arising from this, let the radiographers who will see you at your planning appointment know.

When you practice using the microenema at home, make a note of how long it has taken to have an effect for you as this can vary between people. You will then use this time to inform your preparation for future appointments when following the preparation schedule provided to you.

If you have trouble using the microenema, please tell your radiographer, nurse or doctor.

You should bring two enemas with you each day in case you need to use a second. Let the team know when you only have two left and more will be ordered for you.

What is the maximum time I can leave between emptying my bowel and the appointment?

If it has been more than two hours since you emptied your bowel please tell the radiographers. You may need to use another microenema. There are facilities in the department that you can use for this. If you are travelling by hospital or public transport and you do not feel comfortable or able to use the microenema before travelling, you may prefer to use the microenema at the hospital.

Is there anything else I can do to help my treatment?

We recommend that you drink plenty of fluids throughout your course of treatment. Please do not be tempted to miss meals as this will not help to keep your rectum empty. To help with this, the team can give you information on what food and drinks to avoid before your treatment.

How do I prepare my bowel using laxatives?

Following your consultation where you are referred for radiotherapy, a prescription for laxatives (usually movicol and senna) will be organised for you.

You will usually be asked to use one movicol tablet in the morning and one in the evening as well as one senna tablet each evening each day of the course of laxatives prescribed to you. Your prescription may be changed by the team to best suit your treatment so please always follow the most recent instructions you have been given.