How to choose the best preparation for colonoscopy

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The success and accuracy of colonoscopy is largely dependent on appropriate cleansing of the colon. The ideal bowel preparation should be safe, well-tolerated and effective. Although colonoscopy preparations are vastly better than the earliest barium enemas used in X-ray regimens, none of the currently available formulations sufficiently fulfills the above criteria. Currently used techniques of colon cleansing include dietary and cathartic methods, gut lavage and the administration of phosphates. All of these methods are efficacious, particularly when administered in a split dose (one the evening before and one just before the planned colonoscopy). Gut lavage methods are the safest method; however, dietary and cathartic methods are also reasonably safe. Low-dose phosphate preparations are well tolerated, but safety concerns have led to the withdrawal of some phosphate products from the US market. A new oral sulfate product that achieves a desirable balance of safety, tolerability in patients and efficacy will shortly be introduced. Physicians should be aware of the range of colonoscopy preparations available and their limitations, so that the best preparation can be chosen for an individual patient.

Key Points

  • The importance of adequate colon preparation should be stressed to all patients before their colonic procedure to achieve optimal compliance

  • Adequate colon preparation affords many benefits, such as improved surveillance and decreased study time, rates of complications and risk to the patient, should complications occur

  • Dietary and cathartic methods have relatively few adverse effects, but are less efficacious for colon preparation than other methods

  • Gut lavage, in its various forms, provides effective colon cleansing, but patients have reported volume-related intolerance

  • Phosphates provide effective cleansing with good tolerability, but may have serious adverse outcomes, such as acute kidney injury and metabolic disturbances

  • The ideal colonoscopy preparation, which combines efficacy with excellent tolerability in patients and minimal adverse effects, remains to be developed

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Correspondence to Jack A. Di Palma.

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Competing interests

J. A. Di Palma is a medical director, consultant, has spoken for, and has received grant/research support from Braintree Laboratories, Inc., and is a consultant and is on the speakers bureau for Takeda Pharmaceutical Company Limited. K. E. Occhipinti declared no competing interests.

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