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    Learning About Your Health

    Colonoscopy

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    What is a Colonoscopy?

    A colonoscopy is a test where your doctor looks at the inside of your colon. The doctor can look for abnormalities (things that are not normal). These may include:

    • polyps (small growths that can easily be removed)

    • cancer

    • infections

    • diverticuli (small pouches that are very common but can become infected and cause pain or bleeding)

    • hemorrhoids (large veins that can cause pain when swollen or enlarged)
    The doctor looks at the colon by using a small flexible tube, called an endoscope, that enters the anus and slowly passes into the rectum and colon. It also has small openings to remove polyps or samples with little or no pain.

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    Prepare for Your Colonoscopy

    Your colon must be completely empty and clean to do the test. Your doctor gives you instructions to clean out your colon for your test. This is called "prep". The instructions tell you how to clean out your colon for your colonoscopy. The prep has special directions on foods, drinks, and medicines.

    The prep is very important for the doctor to see the whole colon. Follow the prep carefully.

    • First, check the date for your colonoscopy test.

    • Next, check the date and time the doctor wants you to start your prep. You may need to start your prep 1-2 days before your test.

    • Read the directions for your prep a few days before your test to make sure you understand them. If you have any questions about the prep, please call your doctor's office.

    • If you do not complete the prep before your colonoscopy, you must re-schedule the test.

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    Before Your Colonoscopy

    • DO NOT eat or drink anything after midnight (before the test) unless your doctor tells you otherwise.


    • For your comfort, the doctor gives you medicine before your test that makes you sleepy. You cannot drive or work with machinery until the day after your test.


    • For your safety, make sure someone can drive you home after your test. You may also arrange for medical transportation for a cost. Ask the staff in your doctor's office or check the phone book for more information about this service. Note: If you come to the hospital for your colonoscopy and you have do not have a ride home, you must re-schedule your test.

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    During Your Colonoscopy

    1. You sign a consent form that says you understand the test you are having. This is a good time to ask questions about your test.

    2. Your nurse puts an intravenous line (IV) in a vein in your arm. This is to give you fluid and medicine to make you comfortable.

    3. The nurse asks questions about your health and any medicines you take. Tell your doctor or nurse if you are allergic to any medicines, or if you are taking aspirin or anticoagulant (blood thinning) medicine.

    4. You meet with your doctor right before your colonoscopy. Please tell the doctor about any special needs you may have.

    5. The doctor gives you medicine in your IV that makes you very sleepy and comfortable for the test.

    6. During the colonoscopy, the doctor uses air to expand the colon and look at all the sides. You may feel some pressure and cramping. Tell the doctor or nurse if you are uncomfortable.

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    After Your Colonoscopy

    • You stay in a recovery room for 30 minutes to one hour.


    • Your nurse gives you instructions on how to take care of yourself at home. You will get a written copy to take with you.


    • Your driver (or medical transportation service) needs to pick you up from the GI Lab after your test. The nurse can call your driver and tell them where and what time to pick you up.


    • You may get a survey in the mail about your visit. Please help us by completing the questions.

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    Where to go for Your Colonoscopy

    • You can pre-register for your test by calling (415) 600-0900.

      • If you have pre-registered:
        Go to 3698 California Street, 4th Floor at least 30 minutes before your appointment.


      • If you have not pre-registered:
        Go to 3698 California Street, 1st Floor at least 1 hour before your appointment. Register on the 1st floor then go to the 4th floor GI Lab for your test.
    • When you arrive in the GI Lab, please check in at the reception desk.


    • Parking is available next to the building on Maple Street and at the corner of Cherry and California Streets. The parking garage does not have an elevator. There is a shuttle available. Tell the parking attendant if you need the shuttle. Please allow enough time to park.
    Note: This handout is also available in Chinese, Russian, and Spanish.



    Produced by the Center for Patient and Community Education in association with the staff and physicians at California Pacific Medical Center. Last updated: 9/06


    Funded by: A generous donation from the Mr. and Mrs. Arthur A. Ciocca Foundation.

    Note: This information is not meant to replace any information or personal medical advice which you get directly from your doctor(s). If you have any questions about this information, such as the risks or benefits of the treatment listed, please ask your doctor(s).

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