General information, not an individual diagnosis. Ask a healthcare professional if you are unsure about your situation.
Before a blood test, tell the doctor and laboratory about current or recent biotin use. The cited leaflet explains that it can interfere with some tests. This matters even when the product is not thought of as a medicine.
The cited thyroid-treatment leaflet also calls biotin vitamin B7 or B8. It can be present in some multivitamin mixtures or food supplements. Show the exact ingredients; a ‘vitamins’ label is not a reason to leave this information out.
Depending on the testing method, biotin can produce falsely high or falsely low results. The interference can affect the test itself without meaning that the body has actually undergone the measured change. Not every test is affected in the same way.
The cited thyroid-treatment product information describes this interference in certain tests used to assess thyroid function. A professional should interpret unexpected results with this information, without you diagnosing a disease or changing thyroid treatment on that result alone.
The prescriber and laboratory determine the approach for the test and product used; the product information includes considering an alternative testing method if available. These leaflets do not provide a universal waiting interval that anyone can apply to every biotin exposure and test.
Have the product’s name or pack ready and explain whether you still use it or took it recently. The leaflet says the doctor may ask you to stop it before testing depending on the circumstances. Do not set your own stopping, restarting or test-delay plan: obtain instructions specific to your case.
Sources
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