30 myths about colonoscopy, bowel prep, and colon cancer

Myths about Bowel Prep


  1. There is only one way to prepare the bowel for colonoscopy.

2. All bowel cleansing agents taste awful.

  • Not true. There are several flavored versions of bowel cleansing agents. Some practices use MiraLax plus Gatorade as bowel cleansing agent which does not taste as bad.

3. There is no way to improve the tolerability of bowel preparation.

4. I have to finish my bowel cleansing agent the night before colonoscopy.

  • Not true. The most effective way to consume bowel cleansing agents for morning colonoscopies is the split-dose regimen in which half of the bowel cleansing agent is consumed the night before and the 2nd half is consumed on the morning of the procedure is recommended. For afternoon colonoscopies, you may do the split-dose regimen or consume the entire bowel cleansing agent on the morning of the procedure.

5. I have to stop all medications the day before colonoscopy.

  • Not true. You may continue aspirin and your blood pressure medications prior to colonoscopy. Your provider will give you specific instructions on which medications to continue and which ones to stop.

6. I can’t eat any meal the day before colonoscopy.

  • Not true. Most providers recommend a clear liquid diet the day before your colonoscopy. There are several clear-liquid foods you may consume on the day before your procedure. Read Diet and Colonoscopy.

7. Drinking a little of the bowel cleansing agent should be enough as long as I have bowel movements prior to colonoscopy.

  • Not true. Having some bowel movements prior to colonoscopy does not mean your colon is clean enough for the procedure. You should consume the entire bowel cleansing agent in the recommended fashion prior to your colonoscopy in order to have a good bowel preparation. A good bowel preparation is essential for an effective colonoscopy.

8. I can’t have sweets a day prior to colonoscopy.

  • Not true. Several sweets constitute clear liquid diet and are allowed prior to the day of your colonoscopy. You may have honey, hard candies, sugar, popsicles, fruit ices and sorbet. Read Diet and Colonoscopy.

9. All bowel cleansing agents are large volume purgatives.

10. I can’t handle the side effects of bowel cleansing agents.

Myths about Colonoscopy


11. Colonoscopy is painful.

  • Not true. Most patients say the most unpleasant aspect of colonoscopy is the bowel preparation, not the procedure itself. The majority of colonoscopies are performed under sedation.

12. Colonoscopy is embarrassing.

  • Not true. Great efforts are made by healthcare providers to limit unnecessary exposure. Air is used to distend the colon for better inspection. Passing gas during or after the procedure is common and may help limit cramps from abdominal distention. You are unlikely to have a bowel movement during the procedure as some fear.

13. Colonoscopy takes a long time to complete.

  • Not true. There are 3 main encounters during colonoscopy; pre-colonoscopy, colonoscopy, and post-colonoscopy. The procedure itself usually takes about 15-60 minutes.

14. Colonoscopy has a lot of complications.

  • Not true. Complications from colonoscopy are rare. The risk of perforation is less than 1 per 1,000 colonoscopies. Overall, the risk of serious complication is about 2.8 per 1,000 colonoscopies.

15. Colonoscopy cannot prevent colorectal cancer.

  • Not true. What separates colonoscopy from other tests is its ability to prevent colorectal cancer. This is achieved through the removal of pre-cancerous polyps during colonoscopy. Most of the other tests can only detect cancer.

16. Colonoscopy can only be performed in hospitals.

  • Not true. Colonoscopy can be performed in the office, an ambulatory surgery center or in the hospital.

17. Colonoscopy always requires sedation.

  • Not true. Colonoscopy can be safely performed without sedation.

18. Colonoscopy is usually performed by a surgeon.

  • Not true. Most of the colonoscopies are performed by gastroenterologists. Gastroenterologists are physicians who specialize in the management of diseases of the gastrointestinal tract.

19. Colonoscopy is only used to screen for colorectal cancer.

  • Not true. Colonoscopy can be used to detect and treat many diseases of the lower gastrointestinal tract including diseases of the terminal ileum, colon, and rectum. Other common reasons for colonoscopy include diarrhea, rectal bleeding, and abdominal pain.

20. Colonoscopy is needed every 5 years.

  • Not true. A well done colonoscopy with good bowel preparation should be repeated in 10 years in average-risk individuals. Individuals with personal or family history of colorectal cancer or polyps or those with inflammatory bowel disease often require shorter intervals.

Myths about Colorectal Cancer


21. Colorectal cancer is not preventable.

  • Not true. Colorectal cancer is preventable. Colorectal cancer can be prevented by knowing your family history, getting screened for colorectal cancer, and changing your lifestyle. Read 3 Ways to Prevent Colorectal Cancer.

22. Colorectal cancer only affects men.

23. Colorectal cancer only affects old people.

  • Not true. Colorectal cancer affects young people as well. In fact, colorectal cancer rates for young Americans have been rising.

24. Colorectal cancer is always symptomatic.

  • Not true. A person with colorectal cancer may have no symptoms at all. This is why screening for colorectal cancer is recommended in asymptomatic individuals.

25. Colorectal cancer always requires chemotherapy or radiation.

  • Not true. Cancer confined to the innermost layer of the colon (stage 0, carcinoma in situ) may be removed during colonoscopy. Early stage cancer confined to the colon wall may be removed during surgery without the need for chemotherapy or radiation. Chemotherapy or radiation is only needed for advanced stage colorectal cancer.

26. Colorectal cancer always leads to death.

  • Not true. Colorectal cancer can be successfully treated with surgery, chemotherapy, radiation or a combination of these. Colorectal cancer is not a death sentence. There are many colorectal cancer survivors.

27. Colorectal cancer is most common in white Americans.

  • Not true. African Americans are more likely to develop colorectal cancer or die from colorectal cancer than any other racial or ethnic group.

28. Colorectal cancer is not hereditary.

  • Not true. There are several hereditary forms of colorectal cancer like Lynch syndrome and familial hereditary polyposis.

29. Colorectal cancer surgery always requires a colostomy.

  • Not true. Colorectal cancer surgery can be safely performed without the need for colostomy. The surgery may even be done through laparoscopy.

30. Colorectal cancer does not affect healthy people with regular bowel habits.

  • Not true. Healthy people or people with regular bowel habits may still have colorectal cancer. Colorectal cancer screening is recommended for healthy individuals including those with regular bowel habits.