Alerts

Biotin Found in Multivitamins May Interfere with Important Lab Tests Including hCG and Troponin Levels

SUMMARY:

FDA has released a safety communication (November 2019) to alert health care professionals, lab personnel and consumers to the possible interference of biotin (vitamin B7, Vitamin H, Coenzyme R) with common, clinically significant lab tests, specifically troponin.

Biotin can readily be found in
- Multivitamins, including prenatal multivitamins
- Biotin supplements
- Supplements for hair, skin, and nail growth

Impact of Biotin on Troponin Levels

Troponin is a key biomarker for detecting myocardial necrosis and assessing acute ischemic changes observed with acute coronary syndrome (ACS) and myocardial infarction
The FDA has received adverse events reports indicating that biotin can lead to false negative results
Some companies have addressed this risk while others have not

hCG Levels

While this most recent safety communication is specific to troponin, the FDA does state that “biotin can cause falsely high or falsely low results” in other lab tests as well
- For example, both false positive (FT4 and FT3) and false negative (TSH) thyroid studies have occurred due to elevated biotin levels
One other important example where interference has been documented is hCG pregnancy testing
Biotin can lead to false negative hCG results for both blood and urine pregnancy tests

KEY POINTS:

Biotin Dose

Interference is related to the fact that biotin is a component of certain lab tests, specifically immunoassays based upon biotin-streptavidin interactions
Biotin interference appears to be dose dependent
- Daily recommended allowance for biotin (0.03 mg) should not interfere with lab tests
However, there has been an increase in use of biotin supplementation
- Levels higher than the daily recommended allowance may result in lab test interference
- Some OTC supplements are available with biotin doses >1 mg, particularly those formulations that are marketed around hair, skin and nail quality
- Biotin, up to 300 mg day, may be used by patients with multiple sclerosis

Action Plan

At this point in time, FDA is calling on both the healthcare community and consumers to be aware of false testing results, particularly for troponin
In addition, the FDA has released a list of troponin bioassays that may be subject to interference
Stopping biotin prior to lab testing
- The Alberta Health Services and some health centers in Canada (see Sunnybrook Health Sciences Centre in ‘Learn More – Primary Sources’ below) have sent out an alert and recommend that biotin use be stopped prior to pregnancy testing, troponin and other lab studies if possible | If testing cannot be delayed, the relevant lab should be notified
- Pudek et al. (BCMJ, 2019) recommend stopping biotin 24 hours prior to testing and 1 week if taking high dose
  - ½ life of 0.6 mg biotin dose: <2 hours
  - ½ life of 100 mg to 300 mg: Between 8 and 19 hours
- The FDA, however, states that “sufficient information is not available to know if stopping biotin consumption for any number of hours prior to testing will prevent incorrect test results”
Healthcare professionals should be aware and speak to patients about risk of biotin interference with multivitamin supplements (including prenatal) and supplements for hair, nail and skin improvement
In addition, the FDA recommends that healthcare professionals

Be aware that many lab tests, including but not limited to cardiovascular diagnostic tests and hormone tests, that use biotin technology are potentially affected, and incorrect test results may be generated if there is biotin in the patient’s specimen
Communicate to the lab conducting the testing if your patient is taking biotin
If a lab test result does not match the clinical presentation of your patient, consider biotin interference as a possible source of error
Report to the lab test manufacturer and the FDA if you become aware of a patient experiencing an adverse event following potentially incorrect laboratory test results due to biotin interference