Patient Education

Understanding Bowel Preparation

Your bowel must be clean so that your doctor can thoroughly examine your colon. Many patients feel that the bowel prep is the most difficult part of a colonoscopy. But it is important that you try your best to fully complete the prep.

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Bowel Preparation Before Colonoscopy

It is extremely important that your colon be thoroughly cleaned before your colonoscopy. This will let the doctor see any abnormalities, such as colon polyps, during the procedure. Polyps are small growths in the colon that could later turn into cancer. Cleansing the colon before a colonoscopy is called bowel preparation, or “prep.” It involves taking medication that causes diarrhea, emptying the colon. The medication is taken by mouth, and comes in liquid or tablet form. You will also need to change what you eat during the day or two before the colonoscopy.

What bowel preparations steps are involved before the colonoscopy?

Your doctor will prescribe the type of bowel prep that is best for you. You will receive specific instructions. In general, here is what you can expect:

  • Your doctor will tell you to change your diet at least one day before your colonoscopy. Usually you will need to limit your diet to clear broth, tea, gelatin desserts, ginger ale, sherbet, and clear fruit juices (the ones you can see through), such as apple juice.
  • You need to avoid gelatin desserts and liquids that are red or purple.
  • It is important to avoid dehydration during bowel prep. Drink more fluids than you usually do.
  • Your doctor will tell you exactly when to stop eating and drinking before your colonoscopy.
  • Follow carefully all the steps your doctor prescribes.
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Bowel Prep Medications

Polyethylene glycol; Electrolytes oral solution (PEG-based products) may come as a powder to be mixed with water before use. They are available only by prescription and are taken by mouth. Although given in a greater volume than other products used in bowel prep, PEG-based products are often preferred for patients with kidney, heart and liver conditions. The reason is that they do not cause mineral or fluid changes that can lead to dehydration.

Sodium phosphate comes in tablet form to be taken by mouth and requires a prescription. In rare cases, sodium phosphate can cause kidney failure. Doctors consider this when deciding if sodium phosphate is appropriate for a given patient.

For Your Information:

 IMPROVING DIGESTIVE HEALTH THROUGH EXCELLENCE IN ENDOSCOPY Since its founding in 1941, ASGE has been dedicated to advancing patient care and digestive health by promoting excellence in gastrointestinal endoscopy. This information is the opinion of and provided by the American Society for Gastrointestinal Endoscopy. Gastrointestinal endoscopy helps patients through screening, diagnosis and treatment of digestive diseases. Visit www.asge.org to learn how you can support GI endoscopic research, education and public outreach through a donation to the ASGE Foundation.

Since its founding in 1941, ASGE has been dedicated to advancing patient care and digestive health by promoting excellence in gastrointestinal endoscopy. This information is the opinion of and provided by the American Society for Gastrointestinal Endoscopy.

Gastrointestinal endoscopy helps patients through screening, diagnosis and treatment of digestive diseases. Learn how you can support GI endoscopic research, education and public outreach through a donation to the ASGE Foundation.

For more information visit, www.asge.org or www.screen4coloncancer.org

Copyright © 2018 American Society for Gastrointestinal Endoscopy Important Reminder: This information is intended only to provide general guidance. It does not provide definitive medical advice. It is very important that you consult your doctor about your specific condition.

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