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Fecal Occult Blood Tests

Fecal occult blood tests are valuable for detecting occult blood (hidden GI bleeding), which may be present with colorectal cancer, and for distinguishing between true melena and melena-like stools.
Home tests for fecal occult blood
Most fecal occult blood tests require the patient to collect a specimen of his stool and smear some of it on a slide. In contrast, some new tests don't require the patient to handle stool, making the procedure safer and simplier. One example is a test called ColoCare. If your patient will be performing the ColoCare test at home, include these instructions in your patients teaching:
Avoid red meat and vitamin c supplements for 2 days before the test. Check with doctor about the need to discontinuing medications before the test. Drugs that can interfere with test results incude aspirin, indomethacin, corticosteroids, phenylbutazone, reserpine, dietary supplements, anticancer drugs, and anticoagulants. Flush the toilet twice just before performing the test  to remove any toilet cleaning chemicals from the tank. Next, defecate into the toilet--but to throw no toilet paper into the bowl--- and, within 5 minutes, to remove the test pad from its pouch  and float it printed side up on the surface of the water. Watch the pad for 15 to 30 seconds for evidence of blue or green color changes and recored the results on the reply card. Very important, this test should be performed with three consecutive bowel movements  and then send the completed card to your doctor. Note, if you see a positive color change speak with your doctor immediately.