How do I prepare for my colonoscopy?

How do I prepare for my colonoscopy?

How do I prepare for my colonoscopy?

Before having a colonoscopy, you will need to perform a colon prep, this preparation will empty and clear out your colon because if there is any faecal residue left in the colon, this can obscure the visual for the doctor during the procedure. This colon prep is, in simple terms, a colon cleanse.

Your doctor will most likely send you a detailed list of dietary requirements and guidelines in order for you to prep (cleanse) your colon correctly. If you do not follow these guidelines effectively then the results of your test may be affected. A clear colon allows for clear visuals during the scope and more accurate results.

In order for your colon to be effectively emptied, your doctor may ask you to complete the colon prep which consists of the below factors:

  • Diet - Follow a specific diet a few days before the examination. Normally, the day before the procedure you will not be allowed to eat solid foods and any liquids must be clear, such as tea, water and not milk, broth or any dark coloured carbonated drinks, however, some doctors allow for light, clear broth and clear carbonated beverages. It is also advised that you avoid any red liquids in case they stain the colon or are mistaken for blood in the colon during the exam. In most cases, you will not be allowed to eat or drink anything after midnight of the night before your exam. You will need to stop drinking and eating anything six to eight hours before your colonoscopy.
  • Laxatives - Your doctor will prescribe a laxative that is either in a liquid or pill form for use one day before the procedure. In some situations, your doctor may ask you to take this laxative the night before and the morning of your procedure. Some laxative solutions include PicoPrep, Golytely or Nulytely. Liquid forms of laxatives come in a powder form and need to be mixed with water. These solutions can taste very salty and can often make your stomach cramp and feel mildly to very uncomfortable (depending on the brand used).
  • Enema - Your doctor may also suggest that you use an enema kit to effectively empty your colon. This is likely to be an over-the-counter kit, in which a fluid is injected into your rectum to cleanse your bowel. If this is not administered at home, it may also be administered on the day of your procedure by one of the nursing staff at the hospital.
  • Medications - It is best that you also tell your doctor about any medications that you may be on at least one week before your exam. These include medications for high blood pressure, heart issues or any iron-containing supplements. Your doctor is likely to also recommend that you stop taking any aspirin a few days before your exam. You should also not be taking any medications that may thin your blood, therefore you may need to adjust your dosages or stop these medications temporarily, but this should only be done under your doctor’s supervision.

To allow for your colon/bowel preparation to be a little easier, you can follow the below tips:

  • It may be easier to drink the laxative solution with a straw as this will allow for it to bypass your taste buds and go straight to the back of your throat.
  • Every time you take a dosage of the laxative solution, it may help to also drink something like apple juice to help get rid of the taste it leaves in your mouth.
  • Speak to your doctor about adding any flavoured drink crystals to the laxative solution.
  • You can even add lemon juice to the laxative solution or suck on a lemon wedge after you drink it.
  • Keep the laxative solution in the fridge as drinking it chilled can be more enjoyable. However, your doctor may ask you to drink the solution with warm water and in one go so that it can be easily absorbed (again, this will depend on the prescribed brand).

Your doctor may send you some information along the following lines:

Keep in mind that each doctor is different and may follow a different set of criteria and issue a slightly different guideline. However, the following is provided to give you an idea of what you may expect as well help you to prepare and put your mind at ease about your colonoscopy. This is not to be seen as the guideline that you should follow as your doctor is likely to issue you one.

Bowel prep for your colonoscopy:

Three days before your colonoscopy

This is normally your last opportunity to cancel the procedure, bear in mind that every doctor has a different cancellation policy, so it best that you speak to him to her about this.

Two days before your colonoscopy

Avoid foods containing seeds, nuts or any pips

One day before your colonoscopy


Eat a soft poached or boiled egg with white toast. Do not have any margarine or butter on the toast.

Have some tea or coffee without milk but with sugar if need be. Have a glass of clear liquid every hour after your breakfast.


Mix the first sachet of the laxative given to you from your doctor with 250 millimetres (one cup) of warm water. Stir the mixture well for two minutes and drink it followed by one cup of clear liquid every hour.


Mix the second sachet of laxative with one cup of warm water. Stir for two minutes and follow it with one cup of clear liquid every hour.

The following are acceptable liquids that you may drink:

  • Non-carbonated energy drinks
  • Clear apple juice
  • Vitamin water
  • Clear white grape juice
  • Water
  • Green, orange or yellow jelly

Extra notes to be taken into consideration:

  • Do not drink anything after 23:00 the night before your procedure
  • Your rectum may be raw and extremely sore from the frequent bowel movements - rash cream or ointment can be used for any anal discomfort caused from the laxative.
  • Unless otherwise instructed by your doctor, any medication that is due on the day of the procedure must only be taken once the colonoscopy is finished. Generally, once your doctor has reviewed your medical history and deemed it safe for you to do so:
    • All blood thinners must be discontinued before the procedure
    • Aspirin must be discontinued five days before the procedure
    • Diabetics will be advised to omit their medication on the morning of the procedure

On the day of the colonoscopy

Your doctor may suggest that you bring your own gown and slippers to be comfortable.

Your doctor will also give you a time to be at the hospital for the colonoscopy, this is normally a few hours before the procedure to allow for you to check into the hospital and get prepared for the test.

Post-procedure recovery instructions

Your doctor will likely recommend that you liaise with him or his nursing staff regarding any post-care questions you may have.

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