The U.S. Food and Drug Administration is warning health care providers that biotin, also known as vitamin B7, can significantly interfere with certain lab tests, resulting in incorrect results that may go undetected. Used in hormone tests and tests for certain cardiac health markers such as troponin due to its ability to bond with specific proteins, biotin is also frequently found in multi-vitamins, prenatal vitamins and dietary supplements marketed for hair, nail and skin growth. FDA states that biotin in blood and other samples taken from patients who are ingesting high levels of the substance in dietary supplements can cause “significantly incorrect” test results, both falsely high and falsely low, depending on the test. The agency warns that it has seen an increase in the number of reported adverse events related to biotin interference with lab tests. FDA urges providers to talk to patients about any biotin supplements that may be taking and communicate to the lab conducting testing if a patient is taking biotin. For more, see the FDA Safety Communication.