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Your doctor has suggested that you have a colonoscopy as part of your evaluation at National Jewish Health. A colonoscopy allows the doctor to look inside the colon, or large intestine, using a small flexible tube.

Video: What to Expect From Your Colonoscopy Procedure (Opens in a new window)

Preparing for a Colonoscopy

  • Stop any iron-containing medicines or supplements 7 days before the colonoscopy.
  • Avoid Metamucil and any foods with skins (tomatoes, apples), seeds, corn or nuts for a few days before your test.
  • Purchase a supply of clear liquids for the day before the test. These include Gatorade, fruit juices (no citrus), soda, popsicles without fruit or cream, gelatin without fruit, broth (skim the fat off the top), and black coffee or tea. Do not drink anything that is red, orange or purple.
  • Notify your doctor if you take blood thinners such as Coumadin, Plavix, Lovenox, Pradaxa, etc., as you might need to hold these medications a day or so before your procedure. 
  • Notify your doctor if you take any oral medicines or insulin for diabetes.
  • It is very important that you thoroughly empty your colon so that they doctor can have a clear view.Follow the instructions provided for your specific type of preparation, as there are several types:
  • Stop drinking fluids of any kind 4 hours before your procedure. If you do not follow these instructions, your procedure will be cancelled.

On Procedure Day

  • A responsible adult must wait for you at National Jewish Health during your procedure, and take you back to your residence after you are discharged. You will not be able to drive yourself or take a taxi/public transportation. If you do not have someone with you to drive you home, your procedure will be cancelled. 
  • Check in at the Front Desk, and they will direct you from there. If you have questions, or if you would like to cancel or reschedule your appointment, please call 303-398-1355. 
  • Do not take the medicines your doctor has asked you to hold. 
  • Do take any heart, blood pressure or seizure medicine, with a few sips of water, at least 2 hours before leaving for the test. 
  • Do bring your inhaled medicine with you. If you have sleep apnea, bring your CPAP mask and machine with you. 
  • If you are diabetic, please bring your glucose meter, test strips, and a source of fast-acting glucose with you (such as glucose tablets or glucose gel). 
  • If you use oxygen at home, even if only at night or while active, please bring a portable oxygen unit with you. You may need to use the oxygen for a while after the procedure. The day of the test: 
  • You should not work, drive, or make any important decisions for the rest of the day. 
  • We suggest that someone stay with you overnight.

What is Done during a Colonoscopy?

When you arrive, the nurse will explain what will be done before, during and after your colonoscopy. If you have any questions, please ask. The nurse will start an IV. You will lie down on your left side during the procedure. An anesthesia provider will use your IV to sedate you. Your doctor will insert a flexible scope into your anus and then use it to carefully examine your large intestine. Your doctor may biopsy (remove) small amounts of tissue. The tissue will be studied to help determine your diagnosis and the best treatment for you. You will be monitored closely during the procedure. Once the colonoscopy is complete, you will go to a recovery room to wake up. You will be sleepy in the beginning. Your doctor will determine when you are able to go home. Your nurse will review your procedure report and discharge instructions with you, and send you home with a copy of each. Expect to feel some abdominal cramping for awhile after the procedure.

Length of Test

Plan to be at National Jewish Health for 3 to 4 hours, although sometimes people stay longer. PTE.166 © Copyright Revised 2023