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What to Expect from a Colonoscopy

The Basics

A Colonoscopy is a test using a scope and video that lets your health care professionals examine the lining of your colon and rectum. A Colonoscopy can detect polyps (growths on the lining of the colon and/or rectum) and early cancers. A Colonoscopy is an outpatient screening test performed at a hospital or a clinic. Health-care professionals receive special training to perform the test.

Before the Test

Your health care professional will tell you what foods you can and can’t eat before you take the test. He/she will ask you to clean out your colon and rectum by drinking a special cleansing liquid or by taking oral laxatives. The colon and rectum must be completely clean for the test to be accurate, so be sure to follow your health-care professional’s instructions carefully. You must tell your health care professional about any medications you’re taking. You may be asked to stop taking some of your medications several days before the test.

During the Test

A Colonoscopy rarely causes much pain. You might feel pressure, bloating, or cramping during the test. Your health-care professional will give you a sedative, a medication to help you relax. Some people fall asleep after they have had the sedative. You will be wearing a drape and will lie on your side. Your doctor may put some air into your anus to help him view the colon and rectum. He/she will then slowly move the tube, called a colonoscope, into your anus and through your colon. A picture of your colon and rectum appears on a monitor so that your doctor can see if you have any problems. He/she will look at the lining of your colon and rectum as the colonoscope moves through your colon, and again as it’s slowly removed. The test usually takes 15-30 minutes, but plan on two-three hours for waiting, preparing, and recovering.

What if the Colonoscopy shows something abnormal?

If your doctor thinks something in your colon or rectum needs to be looked at more closely, he might pass an instrument through the colonoscope to obtain a biopsy, a sample of the rectal or colon lining to be examined under a microscope. Biopsies are also used to identify many conditions and your doctor might order one even if he doesn’t suspect cancer. Your doctor might also find polyps during the test and will most likely remove them during the examination. This procedure usually doesn’t cause any pain.

Removing Polyps

Polyps are abnormal growths in the rectum or colon lining that are usually benign, meaning they’re not cancerous. They can be the size of a tiny dot to several inches big. Your health-care professional cannot always tell a benign polyp from a cancerous polyp by the way it looks, that is why he might send the removed polyps to be examined. Because most cancers begin as polyps, removing them is an important way to prevent colorectal cancer. Tiny polyps can be destroyed by burning or removing them with wire loops, called snares, or with biopsy tools. A method called a snare polypectomy may be used to removlarger polyps. This involves passing a wire loop through the colonoscope and removing the polyp from the colon and rectal lining using an electrical current.

After the Test

Your doctor will explain the results to you or an authorized family member or person. You will have to wait several days for the results of the colonoscope and of a biopsy (if one was performed). You may also receive a letter in the mail in about a week with the results of your examination. Immediately after the test, you will be allowed time to recover before you go home. Someone must drive you home and stay with you. Even if you feel awake and alert, your ability to make decisions and your body’s reflexes may not work as they do normally for the rest of the day. You should be able to eat after the examination, although there may be foods your health-care professional will ask you not to eat, and he/she may tell you not to do some of your normal activities, especially after having polyps removed.

Complications of the Test

A Colonoscopy and a polypectomy are generally safe when performed by health-care professionals who have been specially trained and have experience with these techniques. One complication is perforation (or tear) through the colon wall that could require surgery. Bleeding might occur at the place a biopsy is taken, or where a polyp is removed. The bleeding is usually not serious and may be stopped without treatment. Some patients might have a reaction to the sedatives or problems because they have heart or lung disease. Although serious problems are not common. It is important to know warning signs. Call your health-care professional if you notice very bad pain, fever, chills, or rectal bleeding of more than one quarter of a cup. Remember, bleeding can occur several days after the removal of a polyp.