A colonoscopy is an exam of the colon (large intestine, or bowel) with a slim, flexible, lighted tube called a colonoscope. The colonoscope is used to get a clear, magnified view of the inside of your colon from the anus to the area near the appendix.

When is it used?
Colonoscopy is the most direct and complete way to see the entire lining of the colon. It is usually done for one of the following reasons:

How do I prepare for a colonoscopy?
Follow your health care provider's instructions about not smoking before and after the procedure.

If you need a minor pain reliever in the week before the procedure, choose acetaminophen rather than aspirin, ibuprofen, or naproxen. This helps avoid extra bleeding during the procedure. If you are taking daily aspirin for a medical condition, ask your provider if you need to stop taking it before the procedure.

Your health care provider will give you written instructions on how to clear bowel movements from the colon.

Drink plenty of clear liquids during the bowel preparation to avoid dehydration. It is helpful to drink liquids that help replace the electrolytes (potassium and sodium) you lose during the prep. Unless otherwise instructed, you can continue taking your usual medicines.

Tell your provider if:

The test takes 20 to 30 minutes. However, you will need to plan on being at the Endoscopy suite for a total of about one and a half to two hours for check-in, the exam, and recovery. You must arrange for someone to drive you home after the exam.

What happens during the procedure?
Just before your exam, you will be given a sedative, which will help relax you. You will be given this medicine with a needle in your vein (IV).

You will lie on a table on your side with your knees bent and drawn up to your stomach.

The doctor can view the images of the colon on a TV monitor. As the scope is passed through your colon, air is pumped into the colon so your doctor can see as much of the walls of the colon as possible. This air may make you feel bloated and give you cramps.

If your doctor sees anything abnormal during the exam, he or she may take small samples of tissue through the colonoscope for pathology tests. The doctor may be able to remove any abnormal areas, polyps, or small tumors from the colon through the colonoscope.

What happens after the procedure?
After the doctor removes the scope, you will rest until you are awake and alert enough to be driven home. You should plan on continuing to rest for a few hours after you get home. It is normal to have intestinal gas and mild cramps for a few hours after the exam. After resting you should feel like eating a normal diet again. Be sure to drink lots of fluids after the test.

If polyps or other tissue is removed, you may notice a small amount of blood in your stools for a short time.

What are the benefits of this procedure?
This procedure helps your health care provider diagnose problems in the colon. For some problems, such as cancer, treatment is more effective when the problem is detected early.

What are the risks associated with this procedure?
Risks include:

When should I call my health care provider?
Call your provider right away if:

Call during office hours if: