Biotin Side Effects May Interfere With Lab Tests, FDA Warns

Taking high levels of biotin may skew the results of some laboratory tests, causing serious side effects, according to recent warnings issued by federal drug regulators. 

The FDA issued a safety alert November 28, warning both patients and doctors that biotin can interfere with the results of some lab tests. In certain cases, serious side effects may be experienced, including death.

Biotin, or vitamin B7, is a water soluble vitamin commonly used in multivitamins and dietary supplements sold promoting benefits for the nails, hair, and skin. However, many labs also use biotin technology to conduct certain tests.

Biotin bonds with specific proteins, thus helping to detect certain health conditions. It is commonly used in many hormone tests and to test biomarkers for cardiac health.

Because biotin can interfere with the results of certain lab tests, taking amounts above the recommended daily allowance may cause incorrect lab results.

According to the FDA warning, an increasing number of adverse event reports indicate that biotin skewed test results, even resulting in at least one death.

In that case, the patient was taking high levels of biotin and died after lab results falsely indicated low troponin. Troponin is a biomarker which is used to help diagnose heightened risk of heart attack. The patient was misdiagnosed with no risk, and later died as a result of complications from heart troubles.

Biotin can cause both falsely high or falsely low test results. Depending on the test and its purpose, the results may cause a doctor to misdiagnose or mismanage a patient’s health.

The FDA warns both patients and doctors to be aware of biotin interference. Many supplements include biotin in the ingredients, with some supplying up to 650 times the recommended daily intake. While these levels of biotin are not a health risk on their own, taking high levels of biotin and testing for certain illnesses may be unsafe.

The daily recommended allowance for biotin is 0.03 mg. At this level, there is typically no interference with lab tests seen. However, many supplements contain biotin at levels up to 20 mg. In fact, many doctors recommend high levels of biotin, up to 300 mg per day, for certain patient conditions, including multiple sclerosis.

The FDA recommends patients inform their doctor and laboratory prior to testing if they are taking any supplements with biotin, and doctors should always ask patients how much biotin they are taking when ordering lab tests.

Many doctors are unaware exactly how much their patients are taking, so it should always be discussed when conducting lab tests. Doctors should also let the lab know before testing if their patient is taking biotin, the FDA advises.

In the meantime, the agency indicates it is working with laboratories and testing companies to understand how biotin interferes with lab tests, with the hopes of developing recommendations for safe biotin lab testing in the future.

The FDA is requesting that anyone who has experienced side effects as a result of this issue contact the FDA’s MedWatch Adverse Event Reporting program online or by calling 800-332-1088.