Skip to content

    Colorectal Cancer Health Center

    Select An Article

    Fecal Occult Blood Test

    Font Size

    How Should I Prepare for the Fecal Occult Blood Test? continued...

    Do not perform the test if you have:

    1. Diarrhea
    2. Colitis
    3. Constipation
    4. Diverticulitis
    5. Ulcers
    6. Hemorrhoid flare-ups
    7. Your period

    Because certain foods can alter the test results, a special diet is often recommended for 48 to 72 hours before the test.

    The following foods should not be eaten 48 to 72 hours before taking the test:

    • Beets
    • Broccoli
    • Cantaloupe
    • Carrots
    • Cauliflower
    • Cucumbers
    • Grapefruit
    • Horseradish
    • Mushrooms
    • Radishes
    • Red meat (especially meat that is cooked rare)
    • Turnips
    • Vitamin C-enriched foods or beverages

    Your doctor will go over your medicines with you before the test, since you may need to stop taking certain medicines 48 hours before the test.

    How Often Do I Need to Have a Fecal Occult Blood Test?

    To allow for the early detection and prevention of colorectal cancer, the fecal occult blood test is recommended yearly for everyone starting at age 50. This annual test may be recommended along with a flexible sigmoidoscopy and barium enema every five years to check for colorectal polyps or cancer. An alternative is a colonoscopy every 10 years.

    What Do the Fecal Occult Blood Test Results Mean?

    A positive fecal occult blood test means that blood has been found in the stool. Your doctor will have to determine the source of the bleeding, either by doing a colonoscopy, and an upper gastrointestinal endoscopy (EGD) to determine if the bleeding is coming from the stomach or small intestine. If these are negative, swallowing a small capsule (capsule endoscopy) may be performed. This capsule takes pictures of the gastrointestinal tract as it passes through and may see areas of bleeding not seen by other studies, especially in the small intestine.

    A negative test result means that no blood was found in the stool sample during the testing period. You should continue to follow your doctor's recommendations for regular cancer screening.

    WebMD Medical Reference

    Reviewed by Sujana Movva, MD on July 27, 2014
    1 | 2
    Next Article:

    Today on WebMD

    Colorectal cancer cells
    The right diagnosis is the most important factor.
    man with a doctor
    Our health check will steer you in the right direction.
    sauteed cherry tomatoes
    Fight cancer one plate at a time.
    bladder cancer x-ray
    Do you know the warning signs?
    Colon vs Rectal Cancer
    New Colorectal Treatments
    can lack of sleep affect your immune system
    Cancer Facts Quiz
    Virtual Colonoscopy
    Picture of the Colon
    Vitamin D