Proceeds from website advertising help sustain Lab Tests Online. AACC is a not-for-profit organization and does not endorse non-AACC products and services.

Fecal Occult Blood Test and Fecal Immunochemical Test

Print this article
Share this page:
Also known as: FOBT; Stool Occult Blood; Hemoccult; Guaiac Smear Test; gFOBT; Immunochemical FOBT; Immunoassay FOBT; iFOBT; FIT
Formal name: Occult Blood Test, Fecal
Related tests: Complete Blood Count, Calprotectin, Stool DNA

At a Glance

Why Get Tested?

To screen for digestive tract bleeding, which may be an indicator of colon cancer

When to Get Tested?

Annually, beginning at age 50 as part of a routine examination to screen for colon cancer; as directed by your healthcare provider based on your family medical history

Sample Required?

Three stool samples are typically collected over several days and prepared on occult blood cards in order to provide for the most effective screening.

Test Preparation Needed?

For the guiac-based FOBT (gFOBT), you will be instructed to avoid certain medications and follow certain dietary restrictions for several days before collecting the stool samples. For the fecal immunochemical test (FIT), there are no dietary or drug restrictions.