Fecal Occult Blood Test

What Is It?

A fecal occult blood test checks stool samples for traces of blood that cannot be seen with the naked eye. This test is also called a stool guaiac or Hemoccult test. It is a simple chemical test of a stool sample that involves about five minutes of preparation time.

Because the fecal occult blood test can detect bleeding from almost anywhere along the length of the digestive tract, several conditions can cause the result to be positive. They include esophagitis, gastritis, peptic ulcer disease, stomach cancer, ulcerative colitis, colorectal cancer or polyps, and hemorrhoids. The result also can be positive when someone has been taking aspirin or other medications that irritate the digestive tract.

What It's Used For

The fecal occult blood test is used as a screening test to detect colorectal cancer, especially when the cancer is in its early stages and is not causing any symptoms. Doctors often recommend an annual fecal occult blood test for adults beginning at age 50. If you have a higher risk of colorectal cancer because of a personal or family history of colorectal cancer or polyps, your doctor will probably recommend colonoscopy to screen for cancer.

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