What tests is used to detect occult blood?

Occult blood is typically detected using the fecal occult blood test (FOBT), which analyzes stool samples for hidden blood that may indicate gastrointestinal bleeding. There are two main types of FOBT: guaiac-based tests and immunochemical tests (FIT). Guaiac-based tests use a chemical reaction to detect heme, while FIT specifically identifies human hemoglobin. Both tests are commonly used for colorectal cancer screening and diagnosing gastrointestinal disorders.