Colonoscopy is a procedure used to see inside the colon and rectum. It is usually done under sedation. Colonoscopy can detect abnormal tissue, ulcers, and abnormal growths. The procedure is used to look for early signs of colorectal cancer and can help doctors diagnose unexplained changes in bowel habits, abdominal pain, bleeding from the anus, and weight loss.
The US Preventive Services Task Force now recommends screening colonoscopy in all patients at age 45. However, people with an increased risk of colon cancer or those with a family history of colon cancer need to start screening before age 45
What are the colon and rectum?
The colon and rectum comprise the large intestine. Digestive waste enters the colon from the small intestine as a semisolid. As waste moves toward the anus, the colon removes moisture and forms stool. The rectum is about 6 inches long and connects the colon to the anus. Stool leaves the body through the anus. Muscles and nerves in the rectum and anus control bowel movements.
How To Prepare For Your Colonoscopy
The doctor will provide written instructions about how to prepare for the colonoscopy. Usually, you will follow a clear liquid diet for 1-2 days. Patients should not drink beverages containing red or purple dye. Acceptable clear liquids include:
- Fat-free bouillon or broth
- Strained fruit juice
- Plain coffee (no milk)
- Plain tea
- Sports drinks, such as Gatorade
A laxative or an enema will be required the night before colonoscopy to cleanse the colon of all stool remnants.
Patients should inform the doctor of all medical conditions and any medications, vitamins, or supplements taken regularly, including
- arthritis medications
- blood thinners
- diabetes medications
- vitamins that contain iron
Driving is not permitted for 24 hours after colonoscopy to allow the sedative time to wear off. Before the appointment, patients should make plans for a ride home.
Patients who develop any of these rare side effects should contact their doctor immediately:
- severe abdominal pain
- bloody bowel movements