Colonoscopy

Colonoscopy is a test that uses a thin flexible tube with a camera and a light (colonoscope) to look at the inside of the entire colon.

What to expect

Before a colonoscopy, a person will typically be sedated, meaning awake and conscious but sleepy and relaxed during the entire procedure. Intravenous (IV) fluids are started and a pain medication may be given. The person will lie on their left side with knees drawn up toward the chest. Along, flexible, lighted tube (colonoscope) is inserted through the anus and gently moved forward. Air is inserted through the scope to provide a better view. Suction may be used to remove fluid or stool. A small camera mounted on the scope transmits a video image from inside the large intestine to a computer screen. Once the tip of the colon or the last portion of the small intestine is reached, the colonoscope is slowly withdrawn, and the lining of the colon is carefully examined.