Kids Health Info


  • How you say it:
    Colonoscopy: Coal-on-osk-o-pee
    Gastroenterologist: Gas-tro-ent-er-olo-jist
    Gastrointestinal tract: Gas-tro-in-tes-t-nal tract or G.I. tract
    Biopsy: Bye-op-see

    Colonoscopy is a procedure in which a gastroenterologist (specialist doctor) looks at the inside of the large bowel (colon).  This is done by using a long, flexible tube that has a light and a camera on the the end known as a colonoscope.  A gastroscopy is often done at the same time as a colonoscopy.  For more information, see the Kids Health Info factsheet: Gastroscospy.

    The colonoscope is inserted into the bottom (anus) and then slowly advanced along the large bowel. These areas are examined and small samples of bowel tissue (biopsies) are taken.  The main reasons children need a colonoscopy are to find a cause for tummy (abdominal) pain, diarrhoea, and bleeding from the bowel.  If a polyp (an overgrowth of tissue, shaped a bit like a mushroom) is found, a polypectomy may be done at the same time as the colonoscopy.  This involves the removal of the polyp from the inside wall of the bowel.

    Preparing for a colonoscopy

    Special preparation is necessary prior to colonoscopy, as your child's bowel needs to be completely empty in order for the procedure to be successful.  This can usually be done at home.  Sometimes, however, children need to be admitted to hospital the day before in order to have the bowel washout preparation.

    Before having a colonoscopy, the bowel needs to be completely empty. To make sure this happens your child must follow these directions:

    One week before:

    • Stop taking medicines that have iron in them.

    Four days before:

    • Stop eating foods that have small seeds or pips, such as wholegrain bread, tomato, cucumber and nuts.

    The day before:

    • All food and milk must be finished at the time written in your appointment letter.
    • Clear drinks only from the time stated in your appointment letter.

    Clear fluids are drinks you can easily see through including:

    • water
    • clear apple juice
    • lemonade
    • cordial
    • jelly (not red or green)
    • lemonade icy poles
    • weak black tea or coffee
    • Gastrolyte
    • clear sports drinks.

    Clear fluids do NOT include fresh fruit juice and milk.

    It is important that extra clear drinks are given during this time.

     Bowel washout

    • Most children need to have a special drink called a 'bowel washout' the evening before, and sometimes the morning of, a colonoscopy.
    • This drink is very important as it empties the bowel, helping the doctor to see through the colonoscope more clearly.
    • Children who have their bowel washout at home should have extra clear drinks beforehand.
    • If your child cannot take the bowel washout by mouth, they may need to stay in hospital the night before the colonoscopy so that the bowel washout can be given through a nasogastric tube. A nasogastric tube is a small, thin tube which is inserted through the nose and then passed down into the stomach. The bowel washout is then given through this tube over four to six hours.
    • Your child may feel very full and may vomit. They will have diarrhoea for several hours.

    On the day:

    • Your child can continue to have clear drinks only until admission time.
    • All children having a colonoscopy are given a general anaesthetic.  To find out more about anaesthetics, visit the Department of Anaesthesia and Pain Management website: 
    • Most medicines can be taken as usual.  Please talk to your child's doctor about this before the colonoscopy is scheduled.
    • Please contact your child's doctor or the gastroenterology nurse if you have any questions about the instructions to prepare your child for the procedure.

    Care after a colonoscopy

    Eating and drinking
    • Your child can start to eat a light diet such as jelly, soup, pasta and sandwiches as soon as they feel ready.  They may return to their usual diet when they feel well enough.
    • Babies can start breastfeeding, or drinking formula or water, when they are awake.


    • Children can usually go home on the same day as the colonoscopy.  A responsible adult (over 18 years old) must go home with them.
    • Your child should rest for the remainder of the day.
    • Your child should be able to return to their normal activities the next day.
    • Because of the anaesthetic, young adults must not drive a car, operate machinery or make important decisions for the rest of the day.

    Side effects

    Some children may have one or more of the following side effects after the colonoscopy. These usually get better without any special treatment.

    • Nausea or vomiting:   If your child feels sick, stop them from eating and drinking for half an hour.  After this, they can start having sips of clear fluids.  You can then increase what they eat and drink slowly.
    • Abdominal (tummy) pain and bloating:  If the pain is mild, rest and have sips of clear fluids until feeling better.
    • Sore throat:  Sucking throat lozenges or sipping warm fluids can help.
    • Bleeding:  A small amount of blood might be seen in bowel actions (poo).  This is usually caused by the biopsies (small samples of tissue) that were taken.
    • Pain at the injection site.

    When to come back

    Call the RCH switchboard on (03) 9345 5522 and ask to page the gastroenterology doctor on call if:

    • vomited more than tow or three times
    • has a vomit with more than two to three millilitres (half a teaspoon) of bright red blood in it
    • bowel actions (poo) with more than the amount of blood described above
    • severe tummy pain or bloating
    • a high temperature (above 38ºC)
    • difficulty swallowing.


    • Your child's gastroenterologist will speak to you briefly before you go home.
    • Please check that follow-up plans have been made before leaving the hospital.

    Key points to remember

    • The full amount of the bowel washout (drink) must be taken for the colonoscopy to be successful.
    • Contact the hospital if your child is unwell before the colonoscopy, e.g. if they have an infection or a bad cold.
    • Colonoscopy is a very safe procedure, however, your child's doctor will discuss any possible unexpected outcomes with you when taking consent for the procedures.

    For more information

    • Contact the gastroenterology nurse coordinator T: (03) 9345 5082
    • Contact the pre-admission clinic T: (03) 9345 4115

    Individual instructions

    The name of your child's gastroenterologist is:  Dr __________________________



    This factsheet was developed in consultation with the RCH Department of Gastroenterology, Day Surgery Nursing and the Department of Anaesthetics. First published Feb 2005. Updated December 2015.

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This information is intended to support, not replace, discussion with your doctor or healthcare professionals. The authors of these consumer health information handouts have made a considerable effort to ensure the information is accurate, up to date and easy to understand. The Royal Children's Hospital, Melbourne accepts no responsibility for any inaccuracies, information perceived as misleading, or the success of any treatment regimen detailed in these handouts. Information contained in the handouts is updated regularly and therefore you should always check you are referring to the most recent version of the handout. The onus is on you, the user, to ensure that you have downloaded the most up-to-date version of a consumer health information handout.