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Bowel Preparation: Before Your Procedure

What is bowel preparation?

Bowel preparation (or bowel prep) empties and cleans out your large intestine (colon). Bowel prep is done before tests that look inside your colon, such as a colonoscopy. These tests look for small growths (called polyps), cancer, or other problems like bleeding. The colon has to be empty and clean so the doctor can see problems.

For many people, the bowel prep is worse than the test. The liquid you may have to drink can taste bad, and you may feel hungry on the clear liquid diet. You may also spend a lot of time in the washroom.

But it is very important to do the prep exactly as your doctor tells you to. If you do not, the doctor will not be able to see the entire lining of your colon. This may mean that you have to repeat the test and will have to do the prep again.

Follow-up care is a key part of your treatment and safety. Be sure to make and go to all appointments, and call your doctor or nurse call line if you are having problems. It's also a good idea to know your test results and keep a list of the medicines you take.

What happens before the procedure?

Preparing for this procedure can be stressful. This information will help you understand what you can expect and how to safely prepare for your procedure.

Preparing for the procedure

  • 1 to 2 days before the test, you will stop eating solid foods and will drink only clear fluids, such as water, tea, coffee, clear juices, clear broths, flavoured ice pops, and gelatin (such as Jell-O).
    • Do not drink milk or juice with pulp, such as orange juice. These are not clear fluids.
    • Do not drink anything red or purple, such as grape juice or fruit punch.
    • Do not eat red or purple foods, such as grape Popsicles or cherry Jell-O.
    • Drink plenty of clear fluids to stay hydrated.
  • The night before your test, you may have to take a laxative tablet or liquid solution. The solution can taste bad and may make you feel sick to your stomach. But it is important to drink all of it or the doctor may not be able to do the test and you will have to do the prep and test again. Here are some tips:
    • After you drink a dose of the solution, drink some water or clear fluids to help get rid of the salty taste.
    • You may find it easier to drink the solution if you chill it in the refrigerator first.
    • Ask your doctor if it is okay to add flavoured drink crystals (such as Crystal Light) or lemon juice to the solution. Or suck on lemon wedges after you take a drink.
  • Stay home the evening before the test. You will need to use the washroom often.
  • Do not eat any solid foods after you start the bowel prep.
  • Stop drinking clear liquids 6 to 8 hours before the procedure.
  • You will be told which medicines to take or to stop before your procedure. Some medicines, such as aspirin or ibuprofen (Advil, Motrin), and certain vitamins and herbal remedies can increase the risk of bleeding or interact with anesthesia. You may be asked to stop these before the test.

What happens on the day of the procedure?

  • Follow the instructions exactly about when to stop eating and drinking, or your test may be cancelled. If your doctor has told you to take your medicines on the day of the test, do so using only a sip of water.

At the hospital or surgery centre

  • Your doctor may have you use an enema 30 to 60 minutes before the test.

When should you call your doctor?

  • You have questions or concerns.
  • You don't understand how to prepare for your procedure.
  • You think you're having a problem caused by the bowel prep.
  • You become ill before the procedure (such as fever, flu, or a cold).
  • You need to reschedule or have changed your mind about having the procedure.

Where can you learn more?

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Care instructions adapted under license by your healthcare professional. If you have questions about a medical condition or this instruction, always ask your healthcare professional. Healthwise, Incorporated disclaims any warranty or liability for your use of this information.