Colonoscopy

A colonoscopy allows your physician to see inside your large intestine to look for early warning signs of colon or rectal cancer. Using a colonoscope (a flexible, lighted tube designed to travel within the large intestine), abnormal growths can be viewed and removed using special instruments that work through the colonoscope.

What to Expect

Before the procedure, you must drink a laxative to clean out your bowels. This allows the doctor to see the surfaces lining the colon. During the procedure, you will lie on your left side of the examining table. You will be given pain medication and a mild sedative to keep you comfortable and to help you relax during the exam. The physician will insert the colonoscope into your rectum and slowly guide it into your colon. The scope transmits an image of the inside of the colon, so the physician can carefully examine its lining. You may be asked to change position occasionally to help the physician move the scope. The scope also blows air into your colon, which inflates the colon and helps the physician see better.

If anything abnormal is seen in your colon, such as a polyp or inflamed tissue, the physician can remove all or part of it using tiny instruments passed through the scope. That tissue (biopsy) is then sent to a lab for testing. If there is bleeding in the colon, the physician can pass a laser, heater probe, or electrical probe, or inject special medicines through the scope and use it to stop the bleeding.

Colonoscopy takes 30 to 60 minutes. You will need to remain at the endoscopy facility for 1 to 2 hours until the sedative wears off.