The colon must be completely clean for a colonoscopy to be accurate and complete. The colon is prepared by the drinking of a bowel preparation, which will be prescribed by your doctor. Most commonly, the preparation consists of drinking a large amount of nonabsorbable liquid that irrigates the colon (e.g., Golytely, Nulytely). If you find the taste to be unpleasant, sucking on an orange or a lemon after each drink can be helpful. If you prefer to refrigerate the drink, do not refrigerate the entire amount, because if the liquid is too cold, it can dangerously decrease your body temperature. Your physician will give you instructions for the particular prep you will take. If you have questions or difficulties, you should contact your doctor's office.
Although most medications can be continued as usual, some medications such as arthritis medications, anticoagulants, insulin, and iron products may need to be modified. It is therefore important that you inform your physician of all medications you are currently taking, including vitamin supplements. It is also important to inform your physician of any allergies to medications at least 1 week prior to the procedure. Generally, medications such as Coumadin (warfarin), aspirin, Plavix, ibuprofen and several vitamin supplements may increase your risk of bleeding, and you must discuss these with your doctor.
If you have diabetes, your medications need to be changed during the time of the preparation and the day of the procedure, and you should speak to your primary care physician regarding this.
If you have a pacemaker, make sure your doctor is aware of this, as some procedures during colonoscopy require use of a small amount of electricity that may interfere with it.
Except under unusual circumstances, colonoscopy is conducted on an outpatient basis. You will receive instructions from your doctor's office regarding the time your test is scheduled and what time you should arrive at the hospital. Since you will receive intravenous sedation for the procedure, please have a family member or a friend meet you at the hospital after your test to assist you in returning home.
More Answers from Columbia University Department of Surgery