Preparing for a colonoscopy can be more complex and daunting than the actual colonoscopy procedure itself, and it typically includes clearing the bowels with a regimented diet and consuming bowel clearing liquids that instigate diarrhea, according to Harvard Health Publications. If the proper preparation is not performed by the patient leading up to the colonoscopy, it is possible for the doctor to miss polyps or lesions within the colon, and it may also lead to the need for an additional colonoscopy, which implies another round of preparation.
The preparation diet leading up to the colonoscopy typically calls for the patient to switch to a low-fiber diet a few days before the procedure, as stated by Harvard Health Publications. This means the patient should not consume whole grains, nuts, seeds, vegetables or fruits. The day before the procedure, the patient should avoid all solid foods, sticking to a liquid-only diet, including clear broth, tea, clear juice, Jell-O, popsicles or sports drinks. The patient should then fast all foods a couple of hours before the procedure and then follow up the procedure with clear liquids the following day.
The bowel clearing liquids recommended by doctors can include polyethylene glycol or oral sodium phosphate, as listed by Harvard Health Publications. Tablets can also be recommended, such as oral sodium phosphate tablets or over-the-counter magnesium citrate medications.