A colonoscopy is a test that allows your doctor to look inside your large intestine (colon). During the test, a thin, flexible tube about the width of a finger is gently inserted into the anus.

A small camera on the tip of the tube sends images to a video screen. This lets the doctor examine the colon, rectum, and lower intestines and check for growths or other problem areas.

The doctor can also pass small tools through the tube to remove growths or take tissue samples for testing. Some growths, called polyps, can be removed during the procedure. Polyps are common and usually harmless, but some can develop into colorectal cancer over time.

You'll receive sedation during the procedure to help you relax and sleep. A colonoscopy shouldn't hurt, and most people don't remember it.

The truth is that almost everyone needs a colonoscopy at some point. Colonoscopy is the best way to prevent colon cancer. Because colon cancer grows slowly, catching it early through this type of screening test can be a lifesaver.

Most people should have their first colonoscopy around age 45 to screen for colon cancer. After that, you'll typically need a colonoscopy every 10 years, though your doctor may recommend screening more often based on your family history or other risk factors.

If you’re over 45 and haven’t had a colonoscopy in 10 years, you should schedule one. If you’re 75 or older, talk to your doctor about colon cancer screening. You may not need another colonoscopy.

Other options to screen for colorectal cancers include virtual colonoscopy and at-home fecal tests. But you have to do these tests more frequently, and if they show any signs of cancer, you’ll still need a colonoscopy to check and remove any polyps. Learn more about your colon cancer screening options.

We also do a colonoscopy to diagnose digestive disorders. Your doctor may order a colonoscopy for symptoms of inflammatory bowel disease or diverticulitis. They can check for inflamed tissue and ulcers in the rectum and colon.

Concerning symptoms include: 

• Rectal bleeding
• Changes in bowel habits
• Belly pain
• Unexplained weight loss

A colonoscopy is an outpatient procedure. That means you’ll go home the same day. Your colonoscopy may be in the doctor’s office, an outpatient surgery center, or a hospital.

You’ll need to arrange for someone to drive you home as you’ll feel groggy afterwards. 

Before

Your doctor will give you instructions on what to do before your colonoscopy. Following these directions is vital because your bowel needs to be completely clear of stool for the colonoscopy. The process of clearing yourself out is “bowel prep.”

Your care team will give you a bowel prep kit. It might be liquid, pill, or powder to take the night before your colonoscopy.

The bowel prep will give you diarrhea, so make sure you can be close to a bathroom. Most people find that the prep is the worst part of getting a colonoscopy. It’s crucial to finish it because any remaining stool could block your doctor from seeing polyps and other problems.

During

When you arrive at the medical center, you’ll get an IV in your hand or arm for anesthesia and pain relief. You’ll be asleep and won’t be aware of the procedure during the colonoscopy.

You’ll lie on your side on a table where a doctor will insert the colonoscope into your anus. The tube also delivers air to your colon to inflate it. This allows doctors to get a better look inside your colon.

During the procedure, the camera sends images to a video monitor. If your doctor finds abnormal areas, they will take a sample and send it to a lab for testing. If they find polyps, they’ll remove them and send them for testing.

After

You’ll stay in the medical center for about an hour after your colonoscopy as you wait for the sedative to wear off. Your doctor may share the results of your procedure with you. They’ll give you details about follow-up care.

You may have slight cramping or bloating in your belly for the first hour after the colonoscopy.

You can return to normal activities and diet by the next day.

As with any medical procedure, there are some risks to colonoscopy. These are rare and occur more often in older people. 

Risks include:

• Bleeding
• A hole or tear in the colon
• Reaction to the sedative (breathing or heart problems)
• Belly pain