Reasons Why You Might Need To Undergo A Colonoscopy

24 Dec 2020


When it comes to gut health, colonoscopy is something we can’t leave out mentioning. It is a very useful tool for detecting abnormalities in the intestines, including pre-cancerous growths and tumours.

The procedure is a type of endoscopy in which a long, thin, flexible tube is inserted into the body through the rectum. At the end of the tube is a tiny camera that enables the doctor to examine the colon’s interior. Surgical tools can also be inserted through the tube to perform polyp removals or biopsies.

But, unlike some other screening tests that can be undergone annually, colonoscopy is not recommended for frequent testing. So, when is a colonoscopy actually necessary?

Here are some reasons why a doctor may recommend a colonoscopy:

  • To investigate abnormalities in the intestines: When a person experiences gut symptoms like constipation, abdominal pain, rectal bleeding, a doctor may use colonoscopy to examine the intestines for possible causes, such as perforations, growths, blockages, or inflammation.
  • To screen for colon cancer: For a person with no colon cancer symptoms, colonoscopy is sometimes used as a routine screening test. It can also be used to diagnose cancer in patients in which disease is already suspected.
  • Locate and remove polyps: Doctors are able to locate and remove any abnormal growths in the intestine during colonoscopy. Some of these growths may be detected on the spot during routine screening, or by means of other examinations like virtual colonoscopy – in which case, an actual colonoscopy follow-up is needed to remove the detected polyps.

Recommended frequency for colonoscopy

As the risk for colon cancer rises with age, most experts recommend that colonoscopy be performed once every 10 years for those above the age of 50 years. But for persons who have a higher risk of contracting colon cancer (e.g. those with a family history or past experience with polyps), the frequency can be increased to once every 5 years.

The interval between colonoscopies may be reduced in the event that a follow-up colonoscopy is needed. One case that may warrant this includes an incomplete colonoscopy.

Alternatives to colonoscopy

Colonoscopy is widely considered the best screening tool for colon cancer, as it has more reliable detection rates. However, factors like the tedious preparation process, risk of perforation, and discomfort during the procedure are key reasons why colonoscopy is not done more often. So, what about the long 5-10 years in between colonoscopies?

Doctors may recommend other tests and examination methods, depending on your current health concern. A CT colonography can view your intestines ‘virtually’ using X-ray imaging. For suspected rectal bleeding, tests like the faecal immunochemical test (FIT) or the faecal occult blood test (FOBT) can be done. These alternatives are also recommended for those who are not suitable for colonoscopies.


Knowing when to get a colonoscopy done can be key to detecting early cancer or other intestinal health issues. If you have any gut health concerns or are nearing the age where colonoscopy is recommended, do consult your doctor on when’s the best time to get screened.