Bowel washout in hospital

  • A bowel washout is a way of clearing your large bowel (colon) prior to a procedure but is also sometimes used to help with management of constipation.

    Your child will need to have a bowel preparation liquid which causes them to have multiple bowel actions and helps to clean the intestines of its contents (faeces, or poo, and secretions). If your child is having a procedure, this liquid is usually given the evening before.

    A bowel washout is not a painful procedure however the preparation liquid can make your child feel some nausea and they may have mild tummy cramping.

    Some children will be able to have a bowel washout at home, but some may need to come into hospital overnight. Your specialist or nurse will talk to you about which option is more suitable for your child.

    Why does my child need a bowel washout?

    The lining of the bowel continuously produces a substance called mucus. This mucus acts as a lubricant for the passing of faeces (poo). Bowel washouts increase the amount of bowel actions (poos) that your child has, cleaning out all faeces and secretions (mucus).

    Bowel washouts are required for:

    • the management of constipation
    • preparation prior to procedures such as colonoscopy

    For some children with constipation, or conditions that affect their bowel, a bowel washout is needed from time to time to help empty the bowel and manage their condition.

    If your child’s doctor wants to look inside the large bowel with a camera, the mucus can stop the doctor from getting a clear picture. Investigations that your child will need a bowel washout for include a colonoscopy, colonic manometry catheter placement or bowel surgery.

    What to expect with a bowel washout

    Before a bowel washout

    For a bowel washout, your child will need to drink bowel preparation (bowel prep) liquid. This liquid causes your child to have multiple bowel actions, cleaning out all faeces and secretions.

    Depending on the age and weight of your child, they will need to drink between 150 mL to 500 mL of the liquid – for larger volumes, this liquid may be divided into two parts. A gastroenterologist (doctor specialising in the digestive system) will prescribe the amount of solution required.

    Some children are able to drink this at home, however some children cannot tolerate drinking this volume of solution. For these children, admission to hospital the day before their procedure is needed so that the bowel preparation can be given by a nasogastric tube (NGT). A nasogastric tube is a small thin tube that is inserted through the nose, down the throat and passed into the stomach.

    Nasogastric tube insertion

    Insertion of the NGT can sometimes be distressing for children and their parents. Even though having an NGT put in is a short procedure and does not hurt, it is not very pleasant. 

    • Paracetamol or other medicines for pain relief will not stop the discomfort.
    • The nurse will talk to you about the use of sedation for your child to help minimize discomfort and anxiety.
    • Sedation is not mandatory, but does help some children by making them sleepy and relaxed. See our fact sheet Sedation for procedures.

    Once it has been inserted, the NGT is usually held in place by being gently taped to the side of your child's face, near the nostril. Knowing what will happen during the procedure will help make it easier for you and your child. For more about this procedure, see our fact sheet Nasogastric tubes.

    If your child is a patient of The Royal Children’s Hospital, Child life therapists may be available for support during your child’s procedure ­– if you feel that your child would benefit from input from the Child Life Therapy team, please advise your Clinical Nurse Consultant for Gastroenterology, when you receive your appointment time. See our fact sheet Reducing your child’s discomfort during procedures.

    During a bowel washout

    Once the NGT is inserted, the preparation is administered over four to six hours. This is given continuously by an infusion pump that is connected to your child’s NGT. While the solution is infusing, your child will need to remain on the ward. The ward has some activities and each room has a TV for distraction, you are also welcome to bring in your own electronic devices.

    Some children may experience nausea, vomiting or tummy aches while the solution is being given – please let your child’s nurse know if they have any of these effects.  If needed, the rate of the fluid can be slowed or a small break may be given to allow the symptoms to settle.

    Your child will feel a sudden urgency to go to the toilet and empty their bowels, and they should remain close-by to toilet facilities. Your child may experience numerous bowel actions into the night. For toilet trained children, we recommend explaining to them before you come into hospital that they might not get much warning before they need to use the bathroom. Sometimes, accidents happen and we’ll do everything we can to help children make sense of this should it occur.

    If you child is a patient at The Royal Children’s Hospital, wards will provide nappies and dry wipes, however you are welcome to bring in your own supplies (e.g. wet wipes, nappies, pull-ups) if you prefer.

    Having numerous bowel actions can lead to dehydration.  For this reason, children are encouraged to drink clear fluids (e.g. cordial, water, clear apple juice) during the infusion. If they are unable to do so, the nurse will administer a special rehydration solution  via the NGT after the bowel washout has finished.  This solution replaces minerals (electrolytes) and water that your child needs to stay hydrated.

    After a bowel washout

    Your child will need to fast for their procedure on the following day, your nurse will tell you what time fasting will begin.

    The following day your child will be transferred to the operating theatre for their procedure. After their procedure and once your child is awake, the nurses will tell you when your child can eat and drink. Once recovered, you will be discharged home.

    Follow up

    Your child should not require any follow up after a bowel washout. Depending on what the bowel washout was required for, your child’s gastroenterologist or surgeon may schedule a follow up appointment to provide results of any investigations, or to continue management of constipation.

    Key points to remember

    • Bowel washouts are required for:
      • the management of constipation
      • preparation prior to procedures for bowel investigations.
    • Your child will be admitted the afternoon before the procedure.
    • Sedation is available if your child requires it for the insertion of the NGT.
    • Sedation is not mandatory, but does help some children by making them sleepy and relaxed.
    • Your child will have multiple bowel actions into the night.
    • Your child will be discharged home once their investigative procedure is complete.

    For more information

    Common questions our doctors are asked

    Will the washout be painful?

    A bowel washout is not a painful procedure, although your child may experience some cramping or tummy discomfort. It may also make your child feel nauseous for a short period of time and can also sometimes make them vomit.

    Developed by The Royal Children's Hospital Gastroenterology and Clinical Nutrition department. We acknowledge the input of RCH consumers and carers.

    Developed August 2020.

    Kids Health Info is supported by The Royal Children’s Hospital Foundation. To donate, visit


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