False Info about False Positives

The results of a study published in the American Journal of Medicine may change the way you're asked to prepare for a fecal occult blood test (FOBT).

Researchers from Indiana University Medical Center found that the regular use of aspirin or NSAIDs (non-steroidal anti-inflammatory drugs, like ibuprofen) does not cause false positives on fecal occult blood tests. Why is this significant?

Doctors sometimes recommend that people discontinue aspirin or NSAIDs to prevent obtaining a false positive on their FOBT. The point is to prevent a person from having to get a colonoscopy (the recommended step after a positive FOBT) when one isn't necessary.

If you don't need to take aspirin or NSAIDs, then it makes sense not to take any before an FOBT, just in case. But, the researchers say, this study indicates that doctors shouldn't be too concerned about the FOBT getting messed up if someone for whom it's unsafe to discontinue aspirin/NSAID use, continues taking the medicine at the time of the FOBT.

If you're scheduled for a fecal occult blood test, you may want to discuss the findings of this study with your doctor.

_{Source: Kahi, C. and Imperiale, T. "Do Aspirin and Nonsteroidal Anti-Inflammatory Drugs Cause False-Positive Fecal Occult Blood Test Results? A Prospective Study in a Cohort of Veterans." American Journal of Medicine 117.11 (Dec. 2004): 837-841. 25 Aug. 2006.}