What is a Colonoscopy?

A colonoscopy allows the physician to look inside the entire large intestine or colon. The doctor will insert a long, flexible, lighted tube about the size of your finger into your rectum and slowly guide it into your colon. The tube is called a colonoscope (koh-LON-oh-skope). The colonoscope transmits an image of the inside of the colon onto a video screen so the doctor can carefully examine the lining of the colon. The colonoscope is relatively thin and flexible and bends so the doctor can move it around the curves of your colon. This procedure enables the physician to see things such as inflamed tissue, abnormal growths, and ulcers. It is most often used to look for early signs of cancer in the colon and rectum. It is also used to look for causes of unexplained changes in bowel habits and to evaluate symptoms like abdominal pain, rectal bleeding and weight loss.

What Preparation is Required for the Procedure?

A thorough cleansing of the bowel is necessary before a colonoscopy. Your instructions on what you need to do prior to this procedure are on the back of this sheet. The medical staff will also want to know if you have heart disease, lung disease, or any medical condition that may need special attention. You must also arrange for someone to take you home afterward, because you will not be allowed to drive after being sedated. As always, it is important to follow your physician’s instructions very carefully.

What Can I Expect During a Colonoscopy?

For the colonoscopy, you will lie on an exam table on your left side and given a moderate sedative. The physician and a nurse will monitor your vital signs and make adjustments as needed. The doctor will then insert the colonoscope and examine the lining of the colon. The scope blows air into your colon and inflates it, which helps give the physician a better view. When the doctor has finished, the colonoscope is slowly withdrawn while the lining of your bowel is carefully examined and most of the air is removed.

What if an Abnormality is Found During the Colonoscopy?

If your doctor finds an area that needs further evaluation, your physician may take a biopsy to be analyzed by an expert gastrointestinal pathologist. Biopsies are used to identify many conditions, and your doctor may take one even if he or she doesn’t suspect cancer or other related condition.

What Happens After a Colonoscopy?

A colonoscopy usually takes 15 to 30 minutes. The sedative will keep you from feeling any discomfort during the exam. You may feel some cramping or the sensation of having gas after the procedure is completed, but it usually stops within an hour.

What are Possible Complications of a Colonoscopy?

Complications such as bleeding or perforation are rare, but it is important for you to recognize early signs of them. Rarely, people experience severe abdominal pain, fever, bloody bowel movements, dizziness, or weakness after a colonoscopy. If you have any of these side effects, contact your physician immediately. Read your discharge instructions carefully. Medications such as blood-thinners may need to be stopped for a short time after having your colonoscopy, especially if tissue was removed during the procedure. Full recovery by the next day is normal and expected and you may return to your regular activities.

Important Information: The information included on this sheet is intended only to provide general guidance and not as a definitive basis for diagnosis or treatment in any instance. It is extremely important that you consult a physician about your specific condition.

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Screening is the number one way you can reduce your risk of colon cancer. Despite its high incidence, colon cancer is unique in that it is one of the most preventable and, if found early, most treatable forms of cancer.

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