Large intestine, transverse colon, ascending colon, jejunum, descending colon, sigmoid colon, ileum, appendix, rectum, anus
Large intestine, rectum & anus

What should I know or tell my doctor before a colonoscopy?

Be sure to tell your doctor exactly what medicines you take on a daily basis. This includes prescription and over-the-counter products like supplements. Your doctor can tell you which medications to avoid and what changes might be necessary. It is possible that you might have to reschedule your medications if you have diabetes or need blood thinners.

You will need a driver. Most facilities will not let you check in or perform the exam at all if you do not bring a responsible driver with you.

To have a successful colonoscopy, you will have to do your part. This means following all the instructions about what to eat and drink in the days before the procedure. It also means making sure that your colon is empty so your doctor can see clearly when the scope is inside the colon. This involves what is known as ‘bowel preparation.’

Bowel preparation. Colonoscopy prep. Cleaning out your colon. What does this mean?

Your healthcare team will give you plenty of time to prepare. You will get instructions at least two weeks before the procedure. It is important to read and follow all of the instructions given to you. If your bowel is not empty, your colonoscopy will not be successful and may have to be repeated. The cleaner your colon, the better chance your provider will have at finding all of your polyps and cancer, which sometimes can be small or hidden.

What can you eat and drink in the days before a colonoscopy?

Some providers may ask you to avoid corn, nuts, seeds and popcorn for at least three days before the procedure. Others might suggest a low-fiber diet for two days before the colonoscopy. The day before the procedure you will not be able to eat solid food or drink alcohol

You will be able to drink clear liquids, including water, black coffee, tea, ginger ale, apple juice, white grape juice and clear broths. You can have JELL-O® and Popsicles®, but only those that are not red, blue or purple. Drinking extra fluid will help you not become severely dehydrated.

You should not drink or eat anything at all for at least four hours before the colonoscopy. Be sure to drink plenty of fluids the day before while you are doing your bowel prep. If you are having your colonoscopy with general anesthesia, then you cannot drink anything after midnight on the night preceding your test.

What exactly does bowel preparation mean?

There are a few different kinds of bowel preparations, almost all of them liquid. Your doctor will tell you what kind is best for you based on your medical history and their particular preference. Some of these products are prescription-only, while others are available over-the-counter. They all have the same goal—to get rid of everything in your colon by causing watery diarrhea.

The time of day or night that you will have to start drinking the solution will depend on when your procedure is scheduled. You will be asked to consume the entire amount of liquid within a specific time period. There is also something called “split-dosing.” In split dosing, you will be asked to drink half of the bowel preparation the night before and then stop. You will get up in the morning and do the other half of the dose in the morning, finishing up at least four hours before the procedure itself. In general, split dosing results in cleaner bowel preparations. If you are having a colonoscopy with conscious sedation or twilight, and you have not been given split dosing instructions, ask your provider if you can do the split dosing.

What can you do to make a colonoscopy preparation easier?

There are things that might help you to drink the solution more easily. These include using a straw to drink the liquid and cooling the solution in the refrigerator before drinking it. You can add lemon drops or chew ginger candy. You will need to stay close to the bathroom during bowel preparation period. A split-dose might make the preparation easier. You will know you have done a good job when your diarrhea looks clear and yellowish, like urine.

You may experience skin irritation around the anus due to the passage of liquid stools. To prevent and treat skin irritation, you should:

  • Apply Vaseline® or Desitin® ointment to the skin around the anus before drinking the bowel preparation medications. These products can be purchased at any drug store.
  • Wipe the skin after each bowel movement with disposable wet wipes instead of toilet paper. These are found in the toilet paper area of the store.
  • Sit in a bathtub filled with warm water for 10 to 15 minutes after you finish passing a stool. After soaking, blot the skin dry with a soft cloth. Then apply Vaseline or Desitin ointment to the anal area, and place a cotton ball just outside your anus to absorb leaking fluid.

What happens on the day of a colonoscopy?

Take a shower in the morning if you like, but do not use lotions, perfumes, or deodorants. Leave your jewelry, other valuables and contact lenses at home.

During the procedure itself:

  • You are asked to wear a hospital gown and an IV will be started.
  • The procedure can be done with conscious sedation, often referred to as “twilight,” or deeper sedation referred to as “general anesthesia.” You are given a pain reliever and a sedative intravenously (in your vein). You will feel relaxed and somewhat drowsy. This step means that the colonoscopy will not hurt.
  • You will lie on your left side, with your knees drawn up towards your chest.
  • A small amount of air is used to expand the colon so the doctor can see the colon walls.
  • You may feel mild cramping during the procedure. Cramping can be reduced by taking slow, deep breaths.
  • The colonoscope is slowly withdrawn while the lining of your bowel is carefully examined.
  • The procedure lasts about 30 minutes. It takes about 12 minutes to move the scope five or six feet and another 12 minutes to take it out. If there are polyps to remove, the procedure will take longer.

What happens after a colonoscopy?

  • You will stay in a recovery room for observation until you are ready for discharge. The amount of time that you are in recovery depends on whether or not you were sedated and what type of pain management medication you received.
  • You may feel some cramping or a sensation of having gas, but this should pass quickly.
  • Your responsible family member or friend will drive you home.
  • Avoid alcohol, driving and operating machinery for 24 hours following the procedure.
  • Unless otherwise instructed, you may immediately return to your normal diet. It’s recommended that you wait until the day after your procedure to resume normal activities.
  • The doctor performing your colonoscopy will tell you when it’s safe to resume taking your blood thinners or any other medications you might have stopped.
  • If polyps were removed or a biopsy was done, you may notice light rectal bleeding for one to two days after the procedure.

NOTE: If you have a large amount of rectal bleeding, high or persistent fevers, or severe abdominal pain within the next two weeks, go to your local emergency room and call the doctor who performed your exam.

How long will it be before my next bowel movement?

It might take a few days before you have a bowel movement because your colon is empty. It also depends on how much roughage (fibrous foods) you eat.

Last reviewed by a Cleveland Clinic medical professional on 10/27/2019.

References

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