The stool test for occult blood, also called a fecal occult blood test (FOBT) checks the presence of blood in stool that is not visible to the naked eye. Blood in the stool is indicative of some kind of bleeding in the digestive tract which could be indicative of conditions like polyps, ulcers and colorectal cancer.
The fecal occult blood test can only detect the presence or absence of blood, it can't determine what's causing bleeding. This is a simple, inexpensive, and most frequently performed stool test. An FOBT is a screening test that may help find colorectal cancer early when treatment is most effective.
If your test results are positive, additional tests such as a colonoscopy are recommended to figure out the exact location of bleeding.
- Patient should avoid meat products, pain killers, iron tablets, Vitamin C (Ascorbic Acid) and hard tooth brush for 3 days prior to specimen collection.
- Vitamin C when taken in amounts greater than 250 mg per day has been shown to induce false negative results.
- Rectal medications (suppositories) and iron containing medications may also interfere with these tests and should be discontinued two days before and during the test period with the consent of the physician.
- For at least 2 days before and during the test period all raw meat and red meat should be avoided. Raw broccoli, cauliflower, radishes and turnips may cause false positive results, hence should be avoided.