Biotin and lab test interference

CRN Member query:

“Should we be concerned about the potential for interference of biotin with a user’s lab test results? If so, what do FDA and CRN recommend for upper levels of biotin in supplements?”

CRN responds:

The interference of biotin (vitamin B7) with patient lab test results is still a current and real concern. FDA issued a safety warning in 2017 providing some detailed information and background, stating, “Biotin in blood or other samples taken from patients who are ingesting high levels of biotin in dietary supplements can cause clinically significant incorrect lab test results.” You can read the full warning here.

The issue is also highlighted on the National Institutes of Health Office of Dietary Supplements’ website, in both the Biotin Fact Sheet for Consumers and Fact Sheet for Health Professionals, the latter noting that as little as a single dose of 10 mg may result in false lab test results. 

FDA has never given public notice that it has received any reports of adverse effects associated with biotin, and it has not issued an upper level recommendation for the vitamin. CRN recommends 2.5 mg/day as the upper level for biotin in supplements. You can find CRN’s safety recommendations for biotin here.