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 bathroom.

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.

How do you prepare for the procedure?

Procedures can be stressful. This information will help you understand what you can expect. And it will help you 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, flavored ice pops, and gelatin dessert.
  • 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 flavored ice pops or cherry gelatin dessert.
  • 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 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 flavored drink mix or lemon juice to the solution, or if it's okay to suck on lemon wedges after you take a drink.
• Stay home the evening before the test. You will need to use the bathroom often.
• Do not eat any solid foods after you start the bowel prep.
• Your doctor will tell you when to stop drinking clear liquids before the procedure.
• Tell your doctor ALL the medicines, vitamins, supplements, and herbal remedies you take. Some may increase the risk of problems during your procedure. Your doctor will tell you if you should stop taking any of them before the procedure and how soon to do it.

What happens on the day of the procedure?

• Follow the instructions exactly about when to stop eating and drinking, or your test may be canceled. 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 center

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