Fecal Occult Blood Test
Procedure
(FOBT; Stool Occult Blood Test)
Definition
A fecal occult blood test (FOBT) looks for blood in the stool.
Reasons for Test
The test is done to screen for colon and rectal cancers. It may also be done to look for causes of belly pain, diarrhea, vomiting, or lack of hunger.
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Possible Complications
There are no major problems linked to having this test.
What to Expect
Problems To Look Out For
Call your doctor if you have new or worsening symptoms.
If you think you have an emergency, call for medical help right away.
Prior to Test
Your care team may meet with you to talk about:
- Current medicines, herbs, and supplements that you take and whether you need to stop taking them before the test
- Avoiding certain foods in the days leading up to the test
- Not having the test during a menstrual cycle
- Waiting until any hemorrhoids that you may have are no longer bleeding
- Not using toilet bowl cleaners in the days before taking the test
Family Doctor—American Academy of Family Physicians
National Institute on Aging
CANADIAN RESOURCES:
Canadian Digestive Health Foundation
Health Canada
Family Doctor—American Academy of Family Physicians
National Institute on Aging
CANADIAN RESOURCES:
Canadian Digestive Health Foundation
Health Canada
References
- Cobo-Cuenca, A.I., Laredo-Aguilera, J.A., et al. Temporal trends in fecal occult blood test: associated factors (2009-2017). International Journal of Environmental Research and Public Health, 2019; 16 (12): 2120.
- Colorectal cancer screening. EBSCO DynaMed website. Available at: https://www.dynamed.com/prevention/colorectal-cancer-screening.
- Colorectal cancer screening tests. American Cancer Society website. Available at: https://www.cancer.org/cancer/colon-rectal-cancer/detection-diagnosis-staging/screening-tests-used.html.
- Fecal occult blood tests. Cancer.Net website. Available at: https://www.cancer.net/navigating-cancer-care/diagnosing-cancer/tests-and-procedures/fecal-occult-blood-tests.
Contributors
- Marcin Chwistek, MD
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