How can I prepare myself for a colonoscopy?

Your doctor will tell you what dietary restrictions to follow and what cleansing routine to use before your colonoscopy. In general, the preparation consists of limiting your diet to clear liquids the day before and consuming either a large volume of a special cleansing solution or special oral laxatives. The colon must be completely clean for the procedure to be accurate and comprehensive, so be sure to follow your doctor's instructions carefully. 

Dr. Mehmet Oz, MD
Cardiologist (Heart Specialist)

Colonoscopy Survival Guide:

  • Read instructions from your doctor carefully a few days in advance
  • Get all prep materials ready a day before—buy some tasty clear liquids, pops, broths and tea
  • Have lemon wedges on hand to help tolerate the salty bowel prep solution
  • Buy soothing disposable wet wipes and skin creams to protect the anus on hand
  • Make sure family members know that you will need the bathroom at a moments notice
  • If you are prone to constipation try using a gentle laxative and herbal tea for a few days before the actual colon cleansing
  • Exercise to keep things moving
  • Stay hydrated

For at least five days before the colonoscopy examination, do NOT take iron. Speak to your physician for any other medications, especially blood thinners and medicines to control diabetes. 

On the day before the exam, you may need to mix a bowel preparatory solution according to the instructions and refrigerate it for use that evening. Have a clear liquid breakfast. Water, tea, coffee (no milk or cream), soda, broth, clear juice, popsicles and JELL-O are examples of clear liquids. Be sure NOT to ingest red liquids. You’ll want to have a clear liquid lunch and dinner this day, too. In the afternoon, you may have to take a laxative as prescribed by your physician. 

That evening, you’ll most likely have to begin drinking a preparatory solution in advance of your test. Take this as directed. Drink each glass quickly rather than drinking small amounts continuously. Be sure to drink all of the solution recommended. The solution will cause you to have loose stools, which is the expected result. Even if you have liquid diarrhea, please continue taking it. You may have nausea while drinking the solution, but you should drink all of it to ensure an adequate preparation. You may still have loose bowel movements for about 1 to 2 hours after you have completed drinking all of the solution. Continue clear liquids until bedtime.

Check with your individual physician about how to take your regular medications.

On the morning of the examination, you usually can take your regular medications with clear water, unless otherwise instructed by your doctor. Check with your doctor. It is recommended that you DO NOT DRINK ANYTHING starting 4 hours before your scheduled procedure time or the procedure will need to be cancelled. You should plan to have alternate transportation that is flexible as procedures may run longer than expected.

Preparation for a colonoscopy is a personalized regimen arranged by your doctor. Preparation may include medications and bowel preparation.

Dr. Joseph W. Beets, MD

Preparation should begin by getting to know the doctor doing your colonoscopy. All colonoscopies are “not” created equal. Doctors have different training, experience, and outcomes. You should have confidence in the person doing your colonoscopy.

Preparation for colonoscopy is the most difficult part of a colonoscopy. It involves cleaning out the colon so that the doctor is able to visualize the colon itself during the procedure. Everything after the preparation is simple. Preparation is also the most important factor determining the “quality” of a colonoscopy.

If a person is not adequately “cleaned out” for colonoscopy, then it is more difficult to see abnormalities in the colon, and “things” can be missed. Things include polyps and even cancers.

Typical preparation for a colonoscopy includes (details may vary):

  • A period of clear liquids (usually 24 hours before the study).
  • It is important to drink lots of fluids during this liquid-only time.
  • There is usually a large volume laxative or cathartic to drink, which will flush through the colon. People should have about 12-20 bowel movements as they drink the “prep solution.” Stools should look like slightly colored water, or urine, but the completion of the preparation.

If stools are still thick / darkly colored / have debris, the patient should call doctor to describe preparation results. It may be necessary to take additional measures to insure a good prep and allow for a “high quality” colonoscopy.

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Preparing for a colonoscopy may be uncomfortable and time-consuming, but it needn't be an ordeal. Here are some things you can do to help it go as smoothly and comfortably as possible:

  • Get your prep instructions well before your procedure. You'll need to stop certain medications and foods up to a week ahead of time. This is also the time to call your clinician with any questions and to buy the bowel prep formulations she or he has prescribed. When you're at the pharmacy, also pick up some medicated wipes and a skin-soothing product such as Vaseline or Desitin.
  • Arrange for the time and privacy you need to complete the prep with as little stress as possible. Clear your schedule, and be at home on time to start your laxatives.
  • If you're prone to constipation, consult your clinician about using something extra—a laxative such as Correctol, Senokot, or castor oil—to get things going two or three days before the prep. For a week or so before your colonoscopy, discontinue potentially constipating supplements such as calcium, iron, and multivitamins containing either of these minerals. Exercising and drinking plenty of fluids can also help.
  • Keep a variety of clear liquids on hand. On the day before your colonoscopy—when you're restricted to clear liquids—you can have popsicles, Jell-O, clear broth, coffee or tea (without milk or creamer), soft drinks, Italian ice, or Gatorade. But take nothing with red, blue, or purple dye.
  • To make a bad-tasting liquid prep easier to swallow, try one or more of the following: add some Crystal Light or Kool-Aid powder (again, not red, blue, or purple); add some ginger or lime; drink it chilled; drink it through a straw placed far back on your tongue; hold your nose and drink it as quickly as possible; quickly suck on a lemon slice after you finish each glass; hold a lemon or lime under your nose while you drink; suck on a hard candy after each glass.
  • Wear loose clothing, and stay near the bathroom. Better yet, once the preparation starts to work, stay in the bathroom—because when the urge hits, it's hard to hold back.
  • After your bowel has emptied, take a warm bath or shower. Put on some comfortable nightclothes, and get into bed. If you feel chilly or you're having abdominal cramps, place a heating pad or hot-water bottle on your stomach.

The colon must be completely clean for a colonoscopy to be accurate and complete. The colon is prepared by the drinking of a bowel preparation, which will be prescribed by your doctor. Most commonly, the preparation consists of drinking a large amount of nonabsorbable liquid that irrigates the colon (e.g., Golytely, Nulytely). If you find the taste to be unpleasant, sucking on an orange or a lemon after each drink can be helpful. If you prefer to refrigerate the drink, do not refrigerate the entire amount, because if the liquid is too cold, it can dangerously decrease your body temperature. Your physician will give you instructions for the particular prep you will take. If you have questions or difficulties, you should contact your doctor's office.

Although most medications can be continued as usual, some medications such as arthritis medications, anticoagulants, insulin, and iron products may need to be modified. It is therefore important that you inform your physician of all medications you are currently taking, including vitamin supplements. It is also important to inform your physician of any allergies to medications at least 1 week prior to the procedure. Generally, medications such as Coumadin (warfarin), aspirin, Plavix, ibuprofen and several vitamin supplements may increase your risk of bleeding, and you must discuss these with your doctor.

If you have diabetes, your medications need to be changed during the time of the preparation and the day of the procedure, and you should speak to your primary care physician regarding this.

If you have a pacemaker, make sure your doctor is aware of this, as some procedures during colonoscopy require use of a small amount of electricity that may interfere with it.

Except under unusual circumstances, colonoscopy is conducted on an outpatient basis. You will receive instructions from your doctor's office regarding the time your test is scheduled and what time you should arrive at the hospital. Since you will receive intravenous sedation for the procedure, please have a family member or a friend meet you at the hospital after your test to assist you in returning home.

Dr. Daniel M. Labow, MD
Surgical Oncologist

The most important thing to make sure that you go through with the test! Other than that, you need to take a bowel preparation the day before surgery to clean out colon. You may need to stop blood thinners a few days before the test but should consult your physician first.

The night before a colonoscopy, the bowel is purged with medication which can give rise to diarrhea. The day before, the diet is generally limited to clear liquids. On the day of the procedure, aside from the colonic purgative agent, there is nothing else to eat or drink.

To prepare for a colonoscopy you must drink a preparation drink that cleans your colon.

To prepare for a colonoscopy—a screening test for cancer or any polyps in your colon that could become cancer—you will need to clean our your colon before the procedure. On the day before the colonoscopy, you can only consume a liquid diet and then drink a mixture that helps clean out the colon. The better you are able to stick to this regimen, the cleaner the colon and the better job the doctor can do looking (using a flexible scope that has a camera on one end) for cancer or precancerous polyps.

Dr. Walter J. Coyle, MD

A colonoscopy, which is used to detect cancer or precancerous polyps in the colon and diagnose other gastrointestinal issues, requires a certain amount of preparation. Your colon must be completely emptied to give your gastroenterologist an unobstructed view. You will be asked to drink a prep solution that will empty your bowels. Many patients find this to be the least pleasant aspect of the procedure.

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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.