5 Questions You Must Ask Your Doctor About Your Colonoscopy

Neil Gupta, MD, MPH, and Brian Liem, DOBy Neil Gupta, MD
and Brian Liem, DO
Digestive Health Program

A colonoscopy is an important screening method for detecting colon cancer, rectal cancer and other diseases. Although colorectal cancer is among the leading causes of cancer deaths, it is preventable with regular screening and treatable, especially when detected early. Once you’ve decided it’s time to get a screening colonoscopy, the next step is to make sure it is a high-quality test. That means you will need to ask some important questions. Don’t be afraid to raise these issues with your doctor or share any concerns you have.

1. What is your “adenoma” detection rate?

There are different kinds of polyps found during a colonoscopy, including pre-cancerous polyps, called adenomas. Several studies show that a physician is conducting higher quality examinations if they have a higher adenoma detection rate. Physicians with higher adenoma detection rates have patients who are less likely to have colon cancer and to die from colon cancer.

Every physician performing colonoscopies should know his or her adenoma detection rate. A benchmark rate would be at least 25 percent; the higher the rate the better.

2. Will I be taking a split-dose bowel preparation?

A clean colon allows the physician to easily identify polyps, which is why bowel preparation is so important. When you receive the bowel preparation, you should be instructed to take half of the preparation the night before, and the other half the morning of the exam. For years, patients were told to drink all four liters of the preparation solution at once the night before the procedure, but studies show the “split-prep” method has better results. Your doctor will give you directions on how to prepare for your screening.

3. Should I take my prescription medicine as usual?  

Talk to your doctor about whether any of your medications need to be adjusted or stopped temporarily. For example, if you are being treated for diabetes, you may need a different amount of insulin or to hold off taking a medication while your diet is restricted. If you are taking blood thinner medication, you will need to stop taking it before the colonoscopy to prevent bleeding. Call your doctor’s office a few weeks before your scheduled exam to find out what to do. Calling only a few days before will not be enough time.

4. How well did my bowel preparation work?

After the procedure is done, you want to know how clean your colon was. For the best screening, your doctor needs to see the walls of the entire colon. The doctor will rate how clean the walls of your colon were during the screening colonoscopy. If the rating was fair or poor, talk to your doctor about whether you should have a follow-up colonoscopy sooner than you otherwise would.

5. When should I get my follow-up colonoscopy?

The standard follow-up time is 10 years, but your doctor will suggest you have your next test sooner if you are at higher risk of developing colorectal cancer or if polyps were found during the procedure. Even though polyps are removed during a colonoscopy, if a pre-cancerous polyp (adenoma) is found, you are more likely to develop additional precancerous polyps. You may need more frequent screening if you have an inflammatory bowel disease (Crohn’s disease, ulcerative colitis) or if colon cancer runs in your family.

Neil Gupta, MD, MPH, is co-director of the Loyola Medicine digestive health program. He sees patients at Loyola Outpatient Center and the Cardinal Bernardin Cancer Center.

Brian Liem, DO, is a gastroenterologist who sees patients at Loyola Outpatient Center in Maywood.

The digestive health team performs more than 6,000 colonoscopies a year. Digestive health specialists offer a gastrointestinal cancer risk assessment program to help patients find out whether they have a genetic predisposition to GI cancers, such as colon cancer.​

The digestive health program offers colonoscopies at three locations:

Loyola gastroenterologists who routinely perform screening colonoscopies include: