graves disease
2 interactions related to graves disease
methimazole + iodine
Methimazole blocks new thyroid hormone synthesis but does not prevent the gland from using iodide already inside it. Adding a large iodine load (kelp, iodine drops, iodine-containing contrast, amiodarone) can fuel hormone production, blunt methimazole's effect, and in some people worsen hyperthyroidism or, rarely, precipitate thyroid storm.
biotin + thyroid stimulating hormone test
High-dose biotin can interfere with the biotin-streptavidin immunoassays many labs use to measure TSH, free T4, free T3, and thyroglobulin. The result is a falsely low TSH alongside falsely elevated free thyroid hormones, a pattern that can mimic Graves' disease. Published case reports describe patients who were wrongly diagnosed with hyperthyroidism, and started on antithyroid drugs, because of biotin interference that resolved once biotin was stopped.