Do You Take Biotin Supplements? They Could Affect Your Medical Tests

Biotin supplements, often taken to improve hair, skin and nails, can interfere with the results of some critical lab tests, the U.S. Food and Drug Administration warned Tuesday.

The FDA is particularly concerned about biotin interference causing a falsely low result for troponin, which is key in diagnosing a heart attack. The agency said in a statement that it continues to receive reports of cases where biotin interference caused falsely low troponin results.

The FDA first issued a safety communication on this issue in 2017. The agency said that some lab test developers have since reduced biotin interference in their tests, but others have not yet dealt with the problem.

The FDA said it remains concerned about troponin laboratory tests that have not corrected the risk of biotin interference.

In a new update, the agency wants to make the public and health care providers aware of biotin interference with lab tests so that patients, physicians and laboratories can work together to help prevent harmful false test readings.

Biotin is also known as vitamin B7, a water-soluble vitamin. Patients who are currently taking biotin or thinking about taking it should talk to their doctor, and need to be aware that biotin is found in multivitamins, including prenatal multivitamins, biotin supplements, and supplements for hair, skin, and nail growth in levels that may interfere with laboratory tests.

The daily recommended allowance for biotin is 0.03 milligrams (mg), and that amount does not typically cause interference in lab tests.

But biotin levels can vary significantly between products. Those labeled to benefit hair, skin and nails may have high levels of biotin, which may not always be clear from the name of the supplement, according to the FDA.

Many supplements contain 20 mg of biotin and some contain up to 100 mg per pill, with recommendations to take multiple pills per day.

There isn't sufficient information to know if stopping biotin consumption for any number of hours before a test will prevent incorrect test results, the FDA said.

If you have a lab test done and are concerned about the results, talk to your health care provider about the possibility of biotin interference, the agency advised.

Source: U.S. Food and Drug Administration, news release, Nov. 5, 2019.