Colonoscopy FAQs


If a healthcare provider suggests a colon cancer screening for a patient, it does not necessarily mean they think the patient has colon cancer. Screening tests are given when a person has no cancer symptoms in order to prevent colon cancer or catch it in its earliest stages. Once begun, they are typically repeated on a regular basis, which can vary from one year to every 10 years, depending on the patient’s medical history.

Certain habits, behaviors and environments are considered to be risk factors for colon cancer, based on scientific research. The presence of any of these risk factors may lead doctors to recommend a colonoscopy and to determine which screening tests should be used and how often the tests should be performed.

These screenings are a valuable tool for the diagnosis and treatment of many diseases of the large intestine. Abnormalities suspected by X-ray can be confirmed and studied in detail. Even when X-rays are negative, the cause of symptoms such as rectal bleeding or changes in bowel habits may be found through these screenings. Furthermore, while colon cancer is the number two cause of death from cancer in men and women combined, it doesn’t have to be. It is highly preventable with timely screenings.

By choosing to have your colonoscopy procedure at an ASC, you will receive high-quality care in a relaxed environment devoted to individualized patient attention. Benefits include shorter wait times, less congestion and easier parking. An ambulatory surgery center is a more pleasant environment than a hospital at a much lower cost.

A colonoscopy allows a gastroenterologist to examine the interior lining of the colon and inspect for colon polyps, ulcers, tumors or lesions. If any abnormal tissue is found during the examination, the doctor will remove it at that time. If all looks good after the colonoscopy, the patient likely won’t have to schedule another one for 10 years.

One of the best benefits of a colonoscopy is that doctors can remove any suspicious tissue before it has the chance to become cancerous. The diagnostic and preventative qualities of a colonoscopy make it a powerful weapon in preventing colon cancer.

A colon polyp is a small clump of cells that forms on the colon lining. Colon polyps can be raised or flat. Anyone can develop colon polyps. Many middle-aged and older adults have one or more colon polyps, though you’re at a higher risk if you are 50 or older, are overweight or a smoker, eat a high-fat, low-fiber diet, or have a personal or family history of polyps or colon cancer. It’s important to remember that the great majority of colon polyps are harmless, but some can become cancerous over time. Screening is especially important because most polyps don’t cause symptoms. In most cases, the doctor removes colon polyps during flexible sigmoidoscopy or colonoscopy, and then tests them for cancer.

There are complications with any medical procedure. However, colonoscopies are safe and have minimal risk when performed by gastroenterologists, who have been specially trained and are experienced in these procedures.

One rare but serious possible complication is perforation, in which a tear through the colon wall may allow leakage of intestinal fluids. It can be managed with antibiotics and intravenous fluids, although surgery may be required. Bleeding may occur from the site of biopsy or colon polyp removal. It is usually minor and stops on its own. Rarely, transfusions or surgery may be required.

Localized irritation of the vein can occur at the site of medication injection. A tender lump develops, which may remain for several weeks to several months but goes away eventually. Other risks include drug reactions and complications from unrelated diseases such as heart attack or stroke. Death is extremely rare but remains a remote possibility.

In short, complications from these procedures are extremely rare, but they can happen. Your gastroenterologist can tell you more about colonoscopy risks.

For the best possible examination, the colon must be completely empty. The gastroenterologist will give detailed colonoscopy prep instructions that you will follow the day before your procedure, including the use of liquid laxatives and/or pills and fasting that will help ensure your colon is empty of all digested material.

You will be asked to temporarily discontinue the use of aspirin products, iron tablets and possibly other medications before the examination. You should inform the gastroenterologist if you are allergic to any drugs.

You will also need to prepare to have someone available to drive you to and from the appointment. Because of the sedation, you will not be allowed to drive yourself home after the colon cancer screening.

Colonoscopy prep is certainly inconvenient, and the laxative materials you are asked to swallow or drink can make you slightly queasy for a few minutes. This usually does not last long and is a small price to pay to prevent colon cancer.

If prep causes a nauseated feeling, you should inform your gastroenterologist. There are other options available next time that might help alleviate that inconvenience. Check out the colonoscopy prep page for tips and tricks to make the prep day more tolerable.

Wear comfortable, loose clothing the day of the procedure and leave all belts, jewelry and valuables at home.

Bring the following items:

  • Insurance card(s)
  • A driver’s license or two alternate forms of identification if you do not have a driver’s license
  • A friend or family member to drive you home
  • Any change of address, phone or email updates
  • The contact information of your referring physician
  • A current list of all medications and dosages
  • A list of any vitamins, herbs or supplements you are currently taking
  • A list of any known allergies
  • If younger than 18, the patient must have a parent or guardian accompany them to sign paperwork

A colonoscopy typically lasts between 15 and 30 minutes. When the procedure is complete, a nurse will take you into a recovery area, where the sedation will quickly wear off.

You will be monitored until most of the effects of any medication have worn off. You may feel bloated and gassy right after the procedure if any air was introduced into the colon. Once the procedure has been completed, you may resume your usual diet unless instructed otherwise. If polyps have been removed, the doctor may suggest a modified diet and will probably advise you to avoid heavy lifting and exercise for several days.

The procedure itself takes 15 to 30 minutes. Even though you will feel fine, the lingering, subtle effects of the sedation will make it dangerous for you to drive, so a responsible adult must be there to take you home. You should be able to resume normal activities the next day. You may feel some cramping or gas after the exam is completed because of the air used to inflate the colon. This bloated feeling usually subsides within an hour.

Some colon polyps are benign, which means they are not cancerous. However, some types of polyps may already be or can become cancer. Polyps are fairly common in adults, which is why screening is so important. Doctors usually remove colon polyps during a colonoscopy because some of them can turn into colon cancer. Whether or not the polyp is cancerous, it’s important that you have follow-up testing to look for more polyps.

A responsible driver with a valid driver’s license must be available to drive you home because the sedation will impair your ability to drive for 24 hours. The driver should stay at the facility during the procedure. If you don’t have a driver, you will have to reschedule the procedure for a time when you can have an available driver.

Virtual colonoscopy is slowly becoming available, but it is still in its very early stages.

Additionally, a virtual colonoscopy has limitations.

  • It can’t remove colon polyps, and it is not preventive.
  • It doesn’t eliminate the colon-emptying preparation steps; patients must still do that prep.
  • If colon polyps and other abnormalities are seen during a virtual colonoscopy, a traditional colonoscopy must be scheduled to remove them, requiring a second prep and procedure appointment.
  • The amount of radiation received during a virtual colonoscopy is concerning.

Since colon cancer is the second leading cause of cancer death in the US, the recommendation is not to wait to get a colonoscopy if you presently meet the screening guidelines. If no colon polyps are found and if this technology progresses, your next colonoscopy could be a virtual colonoscopy.