Patient Education

Understanding Colonoscopy

Colonoscopy lets your doctor examine the lining of your large intestine (colon) for abnormalities by inserting a thin flexible tube, as thick as your finger, into your anus and slowly advancing it into the rectum and colon. This instrument, called a colonoscope, has its own lens and light source and it allows your doctor to view images on a video monitor.

Gastroenterologist Doctor Tunning endoscope for procedure

Why is colonoscopy recommended?

Colonoscopy may be recommended as a screening test for colorectal cancer. Colorectal cancer is the third leading cause of cancer deaths in the United States. Annually, approximately 150,000 new cases of colorectal cancer are diagnosed in the United States and 50,000 people die from the disease. It has been estimated that increased awareness and screening would save at least 30,000 lives each year. Colonoscopy may also be recommended by your doctor to evaluate for symptoms such as bleeding and chronic diarrhea.

What preparations are required?

Your doctor will tell you what dietary restrictions to follow and what cleansing routine to use. In general, the preparation consists of limiting your diet to clear liquids the day before and consuming either a large volume of a special cleansing solution or special oral laxatives. The colon must be completely clean for the procedure to be accurate and comprehensive, so be sure to follow your doctor’s instructions carefully.

Visual chart of colonoscopy procedure

What happens after a colonoscopy?

You will be monitored until most of the effects of the sedatives have worn off. You might have some cramping or bloating because of the air introduced into the colon during the examination. This should disappear quickly when you pass gas. Your physician will explain the results of the examination to you, although you’ll probably have to wait for the results of any biopsies performed. If you have been given sedatives during the procedure, someone must drive you home and stay with you. Even if you feel alert after the procedure, your judgment and reflexes could be impaired for the rest of the day. You should be able to eat after the examination, but your doctor might restrict your diet and activities, especially after polypectomy. Your doctor will advise you on this.

How are polyps removed?

Your doctor may destroy tiny polyps by fulguration (burning) or by removing them with wire loops called snares or with biopsy instruments. Your doctor will use a technique called “snare polypectomy” to remove larger polyps. Your doctor will pass a wire loop through the colonoscope and remove the polyp from the intestinal wall using an electrical current. You should feel no pain during the polypectomy.

For Your Information:

 IMPROVING DIGESTIVE HEALTH THROUGH EXCELLENCE IN ENDOSCOPY Since its founding in 1941, ASGE has been dedicated to advancing patient care and digestive health by promoting excellence in gastrointestinal endoscopy. This information is the opinion of and provided by the American Society for Gastrointestinal Endoscopy. Gastrointestinal endoscopy helps patients through screening, diagnosis and treatment of digestive diseases. Visit www.asge.org to learn how you can support GI endoscopic research, education and public outreach through a donation to the ASGE Foundation.

Since its founding in 1941, ASGE has been dedicated to advancing patient care and digestive health by promoting excellence in gastrointestinal endoscopy. This information is the opinion of and provided by the American Society for Gastrointestinal Endoscopy.

Gastrointestinal endoscopy helps patients through screening, diagnosis and treatment of digestive diseases. Learn how you can support GI endoscopic research, education and public outreach through a donation to the ASGE Foundation.

For more information visit, www.asge.org or www.screen4coloncancer.org

Copyright © 2018 American Society for Gastrointestinal Endoscopy Important Reminder: This information is intended only to provide general guidance. It does not provide definitive medical advice. It is very important that you consult your doctor about your specific condition.

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