Colonoscopy is an examination of the large intestine, or colon, using a long flexible instrument called a colonoscope. This test may be done for a variety of reasons. Commonly it is done to investigate the finding of blood in the stool, diarrhea, abdominal pain, a change in bowel habits, or an abnormality noted on a colon x-ray or barium enema.

What Happens During the Procedure

An intravenous (IV) will be started in your arm. Just before and during the procedure the nurse anesthetist will carefully monitor you and give you medication which will keep you pain free and unaware during the colonoscopy.

The examination is performed while you are lying on your left side. The doctor will examine your rectum first with a finger and then the colonoscope will be gently inserted. The colonoscope will be carefully passed through the colon and then slowly withdrawn.

If any abnormalities are found, small pieces of tissue may be taken for examination by a pathologist (biopsies). Small growths (polyps) may also be found in the colon and can usually be removed safely. Small bleeding sites are often cauterized (burned) or injected to stop bleeding. This is a very safe procedure and in many cases eliminates the need for major surgery.
This examination may last anywhere from 20 minutes to an hour depending on how long it takes to pass the scope around the colon and treat any abnormalities which are found.

After the Procedure

You will be observed for about 30 minutes before going home. You will not be allowed to drive for the rest of the day.

Following the colonoscopy, the doctor will talk with you and your family and give them a preliminary report of the test findings. A follow-up visit may also be scheduled so the test results can be explained to you when you are fully awake.


This is a very safe examination, but there is a small risk of complications which occur in less than 1% of patients. Reaction to the medications given for sedation are also uncommon, but include allergic reactions, difficulty breathing, or irritation of the vein used to give the medication. Bleeding is a possibility, and can sometimes occur several days after the procedure, especially if a polyp has been removed. Perforation or puncture of the colon may occur. A perforation is a serious problem and in most cases requires hospitalization and surgery in order to repair the perforation of the colon. Fortunately, this complication is quite rare. We continuously monitor blood pressure, pulse, and oxygen levels during the procedure to minimize the risk of any complications related to sedation.

If you experience severe pain, bleeding, or any problems after the procedure, please contact our office immediately.


Colonoscopy is the best test available to detect and treat abnormalities inside the colon. However, like any other medical test, it is not 100% accurate.

Barium enema is a somewhat less accurate X-ray test that can detect many abnormalities in the colon. However, it misses abnormal findings in the colon more often than colonoscopy, and if an abnormality is found, colonoscopy often must be done to biopsy or remove the abnormality.


Complete cleansing of the colon is very important so that a thorough examination of your colon can be performed. Your doctor will chose a laxative preparation for you. Please carefully follow the instructions.

Iron preparations and fiber supplements should not be taken for 4 days before colonoscopy.

If your procedure is scheduled in the morning, you are not to eat, drink, or chew anything after midnight until your procedure is completed. On the day of your procedure, important medications (such as those for high blood pressure or heart disease) should be taken with a small amount of clear liquid early in the morning, at least 3 hours before the procedure. Other medications can be taken after the procedure.

If your procedure is scheduled after noon, you may have one cup of clear liquids of your choice in the early morning and then nothing to eat, drink or chew until after your procedure is completed. You may take your regular prescription medications in the early morning.
If you are a diabetic or taking Coumadin, you will be given specific instructions regarding these medications.

Please let your doctor know if there is any chance you might be pregnant at the time of any procedure.