A colonoscopy is an exam used to detect changes or abnormalities in the large intestine (colon) and rectum.
Investigate intestinal signs and symptoms. A colonoscopy can help your doctor explore possible causes of abdominal pain, rectal bleeding, chronic constipation, chronic diarrhea and other intestinal problems.
Screen for colon cancer. If you're age 50 or older and at average risk of colon cancer — you have no colon cancer risk factors other than age — recommend a colonoscopy every 10 years or sometimes sooner to screen for colon cancer. Colonoscopy is one option for colon cancer screening.
Look for more polyps. If you have had polyps before, may recommend a follow-up colonoscopy to look for and remove any additional polyps. This is done to reduce your risk of colon cancer.
Before a colonoscopy, you'll need to clean out (empty) your colon. Any residue in your colon may obscure the view of your colon and rectum during the exam.
Follow a special diet the day before the exam. Typically, you won't be able to eat solid food the day before the exam. Drinks may be limited to clear liquids — plain water, tea and coffee without milk or cream, broth, and carbonated beverages. Avoid red liquids, which can be confused with blood during the colonoscopy. You may not be able to eat or drink anything after midnight the night before the exam.
Take a laxative. usually recommend taking a laxative, in either pill form or liquid form. You may be instructed to take the laxative the night before your colonoscopy, or you may be asked to use the laxative both the night before and the morning of the procedure.
Use an enema kit. In some cases, you may need to use an over-the-counter enema kit — either the night before the exam or a few hours before the exam — to empty your colon. This is generally only effective in emptying the lower colon and is usually not recommended as a primary way of emptying your colon.
Adjust your medications. Remind your doctor of your medications at least a week before the exam — especially if you have diabetes, high blood pressure or heart problems or if you take medications or supplements that contain iron.
Also tell your doctor if you take aspirin or other medications that thin the blood, such as warfarin; newer anticoagulants, such as dabigatran or rivaroxaban, used to reduce risk of blot clots or stroke; or heart medications that affect platelets, such as clopidogrel.
You may need to adjust your dosages or stop taking the medications temporarily.
During a colonoscopy, you'll wear a gown, but likely nothing else. Sedation is usually recommended. Sometimes a mild sedative is given in pill form. In other cases, the sedative is combined with an intravenous pain medication to minimize any discomfort.
You'll begin the exam lying on your side on the exam table, usually with your knees drawn toward your chest. The doctor will insert a colonoscope into your rectum.
The scope — which is long enough to reach the entire length of your colon — contains a light and a tube (channel) that allows the doctor to pump air into your colon. The air inflates the colon, which provides a better view of the lining of the colon.
When the scope is moved or air is introduced, you may feel abdominal cramping or the urge to have a bowel movement.
The colonoscope also contains a tiny video camera at its tip. The camera sends images to an external monitor so that can study the inside of colon.
The doctor can also insert instruments through the channel to take tissue samples (biopsies) or remove polyps or other areas of abnormal tissue.
A colonoscopy typically takes about 30 to 60 minutes.
Once you reach a certain age, most likely recommend a colonoscopy. This test is not only important for diagnosing colon cancer, but it is also an essential element in the efficient and effective treatment of cancer and other disorders related to your colon, rectum and digestive system.
Colonoscopies are the most effective option for early detection because these tests are capable of picking up small traces of cancer that can quickly spread and become life-threatening.
In most cases, the development of colon cancer begins with a polyp. These small collections of cells form on the lining of the colon. They can vary in shape and size. They are usually benign and harmless, but some will grow, becoming cancerous and very dangerous.
A colonoscopy is not only capable of detecting polyps, but those that look suspicious can also be removed during the actual testing procedure. This not only reduces your risk of developing a form of colorectal cancer, but it also decreases the need for further tests and surgeries to remove cancerous polyps.
Over time, food and bacteria can build up inside the pockets of your intestines, leading to painful inflammation and infections. Known as diverticulitis, the pain and infections may require intense antibiotics and even the removal of a portion of your intestines if the infections are not treated.