A fecal occult blood test checks stool samples for traces of blood that are not visible with the eye. This test is also called a stool guaiac or Hemoccult test. It is a simple chemical test of one to three consecutive stool samples.
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.