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    Colonoscopy

    Colonoscopy



    Test Overview

    Colonoscopy is a test that allows your doctor to look at the inner lining of your Reference large intestine Opens New Window Reference Click here to see an illustration. Opens New Window (rectum and colon). He or she uses a thin, flexible tube called a colonoscope to look at the colon. A colonoscopy helps find Reference ulcers Opens New Window, Reference colon polyps Opens New Window, tumors, and areas of inflammation or bleeding. During a colonoscopy, tissue samples can be collected (Reference biopsy Opens New Window) and abnormal growths can be taken out. Colonoscopy can also be used as a screening test to check for cancer or precancerous growths in the colon or rectum (polyps).

    The colonoscope is a thin, flexible tube that ranges from 48 in. (122 cm) to 72 in. (183 cm) long. A small video camera is attached to the colonoscope so that your doctor can take pictures or video of the large intestine (colon). The colonoscope can be used to look at the whole colon and the lower part of the small intestine. A test called Reference sigmoidoscopy Opens New Window shows only the Reference rectum Opens New Window and the lower part of the colon.

    Before this test, you will need to clean out your colon (colon prep). Colon prep takes 1 to 2 days, depending on which type of prep your doctor recommends. Some preps may be taken the evening before the test. For many people, the prep for a colonoscopy is more trying than the actual test. Plan to stay home during your prep time since you will need to use the bathroom often. The colon prep causes loose, frequent stools and diarrhea so that your colon will be empty for the test. The colon prep may be uncomfortable and you may feel hungry on the clear liquid diet. If you need to drink a special solution as part of your prep, be sure to have clear fruit juices or soft drinks to drink after the prep because the solution tastes salty.

    Colonoscopy is one of many tests that may be used to screen for colon cancer. Other tests include sigmoidoscopy, stool tests, and computed tomographic colonography. Reference Which screening test you choose depends on your risk, your preference, and your doctor. Talk to your doctor about what puts you at risk and what test is best for you.

    Opens New Window Colon Cancer: Which Screening Test Should I Have? Opens New Window


    This information does not replace the advice of a doctor. Healthwise, Incorporated disclaims any warranty or liability for your use of this information. Your use of this information means that you agree to the Reference Terms of Use. Reference How this information was developed to help you make better health decisions.