How you prepareBy Mayo Clinic staff
Before a flexible sigmoidoscopy exam, you'll need to clean out (empty) your colon. Any residue in your colon may obscure the view of your colon and rectum during the exam.
To empty your colon, follow your doctor's instructions carefully. You may be asked to:
- Follow a special diet the day before the exam. Typically, you won't be able to eat the day before the exam. Drinks may be limited to clear liquids — plain water, broth, carbonated beverages and tea and coffee without milk or cream. You may not be able to eat or drink anything after midnight the night before the exam.
- Take a laxative the night before the exam. Your doctor may suggest taking a laxative, either in pill or liquid form.
- Use an enema kit. In some cases, you may need to use an over-the-counter enema kit — either the night before the exam or a few hours before the exam — to empty your colon.
- Adjust your medications. Remind your doctor of your medications at least a week before the exam — especially if you have diabetes, if you take medications or supplements that contain iron, or if you take aspirin or other blood thinners. You may need to adjust your dosages or stop taking the medication temporarily.
- Corbett JV. Laboratory Tests and Diagnostic Procedures With Nursing Diagnoses. 7th ed. Upper Saddle River, N.J.: Pearson/Prentice Hall; 2008:743.
- Levin B, et al. Screening and surveillance for the early detection of colorectal cancer and adenomatous polyps, 2008: A joint guideline from the American Cancer Society, the US Multi-Society Task Force on Colorectal Cancer, and the American College of Radiology. Gastroenterology. 2008;134:1570.
- Colorectal cancer screening. Bloomington, Minn.: Institute for Clinical Systems Improvement. http://www.icsi.org/guidelines_and_more/gl_os_prot/preventive_health_maintenance/colorectal_cancer_screening/colorectal_cancer_screening_6.html. Accessed May 2, 2011.
- Flexible sigmoidoscopy. National Institute for Diabetes and Digestive and Kidney Diseases. http://digestive.niddk.nih.gov/ddiseases/pubs/sigmoidoscopy/index.htm. Accessed April 29, 2011.