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Why I Do a Colonoscopy
This important examination can find problems and head off deadly cancer.
Many people worry about having their large bowel examined with a colonoscope. While anxiety is normal, the colonoscope is an amazing instrument that gives gastroenterologists like me a very close view of the large bowel, also called the colon.
It helps me see problems such as inflammation or bleeding, and it might save your life if I find a tumor or the tiny, precancerous growths called polyps.
I recommend colonoscopies for several reasons:
A major, consistent shift in bowel habits, such as constipation, diarrhea, changes in stool size or shape, and a lot more or fewer bowel movements than normal for you
Bleeding during bowel movements
Unexplained weight loss
Persistent abdominal pain
A family history of colorectal cancer
An age of 50 or older
Usually, I'm looking for hemorrhoids, diverticular disease, inflammatory bowel disease, an obstruction, or some other problem. Always, I'm vigilant for signs of cancer and for polyps.
If we remove a polyp before it becomes cancerous, or in cancer's earliest stages, we reduce or eliminate your odds of developing colorectal cancer.
My staff will give you a laxative to take the night before the exam, and we'll tell you when you can eat or drink.
Before your exam, you'll get an intravenous sedative. I use a lighted, flexible colonoscope about the diameter of an index finger to examine the rectum and colon, which I view on a video monitor. The exam lasts 15 to 45 minutes, depending on what I find and the colon's length, which varies from three to six feet.
You might feel discomfort when we inflate the colon slightly with air so we can better use the colonoscope. We can adjust the sedative to limit discomfort.
I'll remove polyps for testing and take photographs so I can compare your colon with exams done years later or before. Ask your doctor how often you should repeat this test.
Source: Leo C. Katz, M.D., a gastroenterologist in Philadelphia
Online ResourcesNational Institute of Diabetes and Digestive and Kidney Diseases http://digestive.niddk.nih.gov/ddiseases/pubs/colonoscopy/
American Cancer Society http://www.cancer.org/cancer/colonandrectumcancer/detailedguide/colorectal-cancer-detection