Preparing for a colonoscopy

Diet, tips, and instructions for a smooth colonoscopy prep.

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If you shudder at the thought of having a colonoscopy to check for hidden colon cancer, chances are it's the prep that's stoking your apprehension. It's certainly a major inconvenience: getting ready for the procedure takes much longer — an average of 16 hours, according to one study — than the three hours or so you'll spend at a medical center the day of your colonoscopy. But what's most off-putting is the purgative part: taking a powerful bowel-clearing substance and coping with the resulting diarrhea.

It's worth the hassle. Colonoscopy can spot small colon cancers while they are treatable and before they have spread to other parts of the body. It can also detect and remove polyps, small growths that can develop into colon cancer. Colon and rectal cancers (known together as colorectal cancers) are the third most common type of cancer in men and in women, and the second leading cause of cancer-related deaths in the United States.

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