Healthy Living

What Are The Risk Factors Of A Colonoscopy?

What Are The Risk Factors Of A Colonoscopy?

Colonoscopy is a medical procedure and like all medical procedures, it may have its risks. For a vast majority of patients, the benefits far outweigh the risks and also much can be done to minimize the risks.

About Colonoscopy

The colonoscopy procedure involves the use of a thin and flexible camera that helps to detect any problems in the large intestines. The large intestine is the last section of the gastrointestinal tract that carries out the important function of receiving food, absorbing its nutrients and eliminating waste from the body. The rectum is the last part of the large intestine that connects the colon to the anus.

It is also possible to take sample tissues for biopsy or abnormal tissues like polyps through a colonoscopy.

Why you need the procedure

This procedure is normally performed to look for colon cancer and other complications. It will help the doctor:

  • Diagnose the underlying reason of the diarrhea, loss of weight or chronic constipation
  • Assess for cancer signs and other complications
  • Inspect bleeding or pain symptoms in the abdominal section
  • Identify any changes in bowel routines

It is recommended that people above the age of 50 go through a colonoscopy once in 10 years, as their chances of developing colon cancer are average. if you're at high risk for colon cancer, you may have to undergo the procedure quite often. Research indicates that approximately 90% of colon cancer cases can be avoided by undergoing a colonoscopy.

Risks of Colonoscopy

Colonoscopy is a regular procedure so it poses minimal risks. The benefit of detecting complications and beginning treatment quickly overshadows associated risks in many cases.

This procedure is generally carried out by a gastroenterologist, a doctor who specializes in ailments of the digestive system and its disorders. Some surgeons also hold qualifications to perform colonoscopies.

It is in your interest to ensure that the doctor performing your colonoscopy is highly qualified and experienced in this procedure. Hence, do not let costs be the basis on deciding where to have your procedure performed. Choosing highly reputed centers to have your colonoscopy will minimize your risks. Make sure your doctor can be easily contacted after hours, so that if you have any questions before and after the procedure, you can contact them.

It is important to discuss all your concerns with the doctor. Do not hesitate to enquire about the procedure, its risks, the meaning of the results and so on. Make sure you clarify all your queries.

You can minimize potential risks by ensuring that you do the following before the colonoscopy:

  • Arrive for the procedure with a clean colon. This can be done by carefully following the instructions given by the doctor.
  • If any literature or material has been given to you, ensure you read it carefully
  • If you are being treated for any other medical condition or medication, be sure to inform your doctor about it. Check with your doctor on how to take these medications on the day of your test.

Complications may arise occasionally, which include:

  • Sedative reaction
  • The bigger the polyps, the bigger the risk
  • Bleeding in the area where the biopsy was done
  • Tearing of the colon or rectal wall
  • Dysbiosis: is an imbalance in your gut flora caused by too few beneficial bacteria and an overgrowth of bad bacteria, yeast, and/or parasites.In colonoscopy, the colon is thoroughly washed out with large doses of synthetic laxatives, a bowel irrigation using hypertonic electrolytes and polyethylene glycol, which can disrupt intestinal flora. These substances destroy good and bad bacteria. Dysbiosis causes constipation, irregularity, Crohn’s disease, IBS and other disorders that are responsible for raising the risk of colon cancer.
  • Deteriorating stool patterns: Individuals with existing IBS, hemorrhoids, diverticulosis or chronic constipation report worsening of these disorders after undergoing a colonoscopy.
  • Problems resulting from the procedure:  Severe problems like perforation of the colon happen in every 5 in 1000 procedures. There are high chances of developing ulcers, infections and bleeding although they do not happen a lot.
  • High chances of heart attack, stroke and pulmonary embolisms: Anesthesia can lead to blood clotting especially in individuals suffering from heart disorders and diabetes.
  • Infection: Infections like pyelonephritis and pneumonia are linked to procedures that involve anesthesia.

Many of these risks rarely occur, and in cases which do not involve removal of polyps, the risks in fact are minimal. However, it is important to call your doctor immediately in case you have any of these symptoms after the procedure:

  • Develop a fever
  • Have severe stomach pain
  • Feeling dizzy and nauseous
  • Have heavy rectal bleeding
  • Have a swollen and firm belly


The doctor will instruct you to do a bowel preparation. Before the procedure, your diet has to consist of clear fluids for a minimum of 24 hours. These may include:

  • Sports drinks
  • Tea or coffee
  • Gelatin
  • Broth or bouillon
  • Juice without pulp

Since liquids with purple or red color can discolor the large intestines, they are not recommended.

Inform the doctor of any drugs you may be using such as supplements or over-the-counter medicines. You may be instructed to quit using them if they can affect the procedure. These include iron-rich vitamins, blood thinners and some drugs for diabetes.

You may be given a laxative the night prior to the procedure. You will then be asked to use an enema the day of the colonoscopy.

Since you will not be able to drive because of the sedatives used during the procedure, make plans to have someone drive you home afterwards.

In most cases, more polyps are missed than detected

In almost one third of all colonoscopies done, cancerous tumors and polyps are missed. Also, there is a major risk of cancer from the radiation used during the procedure.  


Colorectal cancers are preventable cancers. Regular screening helps not only to prevent cancer but early detection, that is detecting the cancer when it is smaller also makes it easier to treat. Since early colorectal cancers don’t cause any noticeable symptoms, people may be reluctant to go for regular screening. What happens then is that the cancer advances and may be difficult to treat. Therefore, early screening is the key to prevention of colorectal cancers.

Colonoscopy agitates people and makes them wary of the procedure. People need to be aware of all the factors that contribute to the risk pertaining to colonoscopy.