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Colonoscopy

How It Is Done

Colonoscopy may be done in a doctor's office, clinic, or a hospital. The test is most often done by a doctor who works with problems of the digestive system (gastroenterologist). The doctor may also have an assistant. Some family doctors, internists, and surgeons are also trained to do colonoscopy.

During the test, you may get a pain medicine and a sedative put in a vein in your arm (IV). These medicines help you relax and feel sleepy during the test. You may not remember much about the test.

Before the test

You will need to take off most of your clothes. You will be given a gown to wear during the test.

You may lie on your left side with your knees pulled up to your belly. Because you will be given medicine during the colonoscopy, you probably won't remember much, if anything, until you wake up after the procedure.

Next, the doctor will insert a thin, flexible colonoscope in your anus and move it slowly through the rectum and into your colon. Air will be used to inflate your colon so the doctor can look at the lining of the colon through the scope slideshow.gif or on a computer screen hooked to the scope.

During the test

You may feel the need to have a bowel movement while the scope is in your colon. You may also feel some cramping. Breathe deeply and slowly through your mouth to relax your belly muscles. This should help the cramping. You will likely feel and hear some air escape around the scope. There is no need to be embarrassed about it. The passing of air is expected. You may be asked to change your position during the test.

Your doctor will look at the whole length of your colon as the scope is gently moved in and then out of your colon.

The doctor may also use tiny tools, such as forceps, loops, or swabs, through the scope to collect tissue samples (biopsy) or take out growths. Usually, people do not feel anything if a biopsy is done or if polyps are taken out.

The scope is slowly pulled out of your anus and the air escapes. Your anal area will be cleaned with tissues. If you are having cramps, passing gas may help relieve them.

The test usually takes 30 to 45 minutes, but it may take longer, depending upon what is found and what is done during the test.

After the test

After the test, you may need to stay at the clinic for 1 to 2 hours. Or you may be allowed to leave sooner with the person who will be driving you home. Your doctor will tell you when you can eat your normal diet and do your normal activities. Drink a lot of fluid after the test to replace the fluids you may have lost during the colon prep, but do not drink alcohol.

If you received a sedative during the test, do not drive, operate machinery, or sign legal documents for 24 hours after the test. Arrange to have someone drive you home after the test.

WebMD Medical Reference from Healthwise

Last Updated: October 30, 2013
This information is not intended to replace the advice of a doctor. Healthwise disclaims any liability for the decisions you make based on this information.

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