Colonoscopy lets the physician look inside your entire large intestine, from the lowest part, the rectum, all the way through the colon to the lower end of the small intestine. The procedure is used to diagnose the causes of unexplained changes in bowel habits, signs of cancer in the colon and rectum, inflamed tissue, abnormal growths, ulcer, bleeding, and muscle spasms.

For the procedure, you will lie on your left side on the examining table. You will be given medication to keep you comfortable and to sedate you during the exam. The physician will insert a long, flexible tube into your rectum and slowly guide it through your colon. The scope also blows air into your colon, which inflates the colon and helps the physician see better. Most of the air is removed after the examination is finished.

If anything unusual is in your colon, like a polyp or inflamed tissue, the physician can remove it using tiny instruments passed through the scope. That tissue (biopsy) is then sent to a lab for testing. If there is bleeding in the colon, the physician can use instruments through the scope to stop the bleeding.

Your colon must be completely empty for the colonoscopy to be thorough and safe. To prepare for the procedure, you must follow a clear liquid diet and use a laxative solution on the day before the procedure. A clear liquid diet means fat-free bouillon or broth, Jello or Popsicles (any color except red, blue, purple or orange), strained fruit juice, water, plain coffee, plain tea, or soda (any kind). Please see the colonoscopy preparation instructions for complete details.

Colonoscopy takes 10-45 minutes; however, you will need to plan to be at the hospital for 2 1/2-3 hours. The medicine given for sedation should keep you from feeling discomfort during the exam. The majority of patients remember nothing about the procedure.

You will need to remain at the hospital for approximately one hour afterward, until the medication wears off. Also, you must arrange for someone to take you home afterward-- you will not be allowed to drive because of the sedative. You may resume your normal diet after the procedure. The day after the procedure, you may return to work or school and your other normal activities; however, if biopsies were taken, you will need to avoid heavy lifting (over 25 pounds). Your physician may give you other special instructions.