Colonoscopy Side Effects

Side Effects Of Colonoscopy

In most cases side effects of colonoscopy are negligible or absent altogether. A colonoscopy should not be confused with the removal of part or all of the colon, or with any major surgery on the colon. A colonoscopy is an examination of the colon, and since it is an examination, one would not expect any side effects of colonoscopy to manifest themselves.

Nevertheless, there are occasional side effects, and in a small percentage of these procedures, probably less than 1%, there may be severe or serious side effects or complications. The patient is anesthetized, which always carries with it a certain amount of risk, and a tube with a camera is run through the colon. This could lead to a risk of colon damage or perforation. If a polyp is located it is likely to be removed, usually for the purpose of conducting a biopsy, or because of its size. This procedure can carry a small risk of infection or bleeding.

Occasionally, a disorder in the colon may be treated during the colonoscopy, but generally, except for removal of polyps, such a treatment would be done separately. Obviously, the more procedures that are undertaken, and the longer the overall procedure lasts, the greater the chances are that side effects of colonoscopy might occur.

Most Side Effects Mild Or Preventable - Some of the more common side effects of colonoscopy are for the most part preventable if the patient is given the rules for preparing for the procedure and follows those rules. For example, side effects such as infections from particles of digested food or stool in the colon should never happen as the colon should be completely cleansed prior to the procedure. This is usually done by drinking fairly large doses of a colon cleanser/laxative the day before the procedure. This cleansing activity, coupled with a need to fast, is usually the most unpleasant aspect of a colonoscopy from the patient's point of view.

Following a colonoscopy, bloating sometime occurs during the first stages of recovery, but seldom causes more than mild discomfort and usually does not last long. There may be some intestinal bleeding if a large polyp has been removed, but this will generally subside rather quickly as well. Any time a polyp is removed, there exists a possibility of infection, but if the colon has been cleansed, and antibiotics are administered, infection rarely becomes a concern. In most cases when a polyp is removed, the wound is cauterized by heat from the electrical wire used to lasso and remove the polyp, so bleeding is actually somewhat rare, as is the chance for infection.

More A Problem With The Elderly - The more serious side effects of colonoscopy  are most likely to occur among elderly patients, partly because symptoms of minor side effects sometimes tend to be magnified in the elderly, partly because preparation for the procedure may cause dehydration, and sometimes because elderly patients are more apt to become physically stressed during the procedure. Colonoscopies are seldom performed on people over 75 years of age unless there appears to be a very good reason for the examination. If the colon is clean and free of suspicious polyps or other problems when a person is in their early 70's, it is usually assumed that anything that may happen is not too apt to adversely affect them during their remaining years.


A colonoscopy is something that is not to be feared. Even if a patient is not totally anesthetized, he or she usually will not remember any of the procedure. In any event, it is painless, even if polyps need to be removed, and over 95% of the time recovery is quick and rather routine, with the patient advised to take it easy for a day and not to drive themselves home. Again, the worst part of the whole process is in the preparation stage, where trying to drink the colon cleanser/laxative solution when you already feel quite full can be a challenge. As one doctor put it, “the feeling you can't drink another drop is all in the mind”.