@caroljeand This is what I have found: What type of tests are potentially affected?
The Food and Drug Administration (FDA) has published a warning regarding the possible interference of Biotin supplementation with a few specific laboratory tests. Tests that are typically used for the evaluation of endocrine function, including but not limited to PTH (parathyroid hormone), TSH (thyrotropin), fT4 (free thyroxine), TT3 (total triiodothyronine), and Tg (thyroglobulin); as well as other tests such as troponin, serum folate, vitamin D, and hepatitis A & B antibodies may produce inaccurate results when someone is taking a Biotin supplement. Some of these tests are at risk of producing results that are falsely too high or too low when Biotin is present in the tested sample.