Early tomorrow I am having a comprehensive thyroid blood test (ie tsh, t3, t4 plus vitamins etc). I am confused about whether to take levothyroxine before the test or not. There seems to be so much conflicting information on this subject. Thanks for any comments.
thyroid blood test tomorrow: Early tomorrow I am... - Thyroid UK
thyroid blood test tomorrow
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Hello Levo1 ! Based on the excellent advice from the knowledgeable folks on here, you need to have at least 24 hours between your last dose of levothyroxine and your blood test.
So if you take your levothyroxine in the morning and you took it this morning, then you should NOT take tomorrow's dose before the blood test. You should wait to take your next dose until AFTER the blood test (e.g. blood test at 8:30am, take levothyroxine at 9:00am, for example).
lots of info (and proper references to back up the reasons why things are recommended) in this post:
healthunlocked.com/thyroidu... suggested-thyroid-hormone-test-timing-protocols
You want consistent tests taken under same conditions each time as far as is possible , ideally... early am test / last dose Levo approx 24hrs previous.
but whatever you decide to do about dose time / test time/ fasting or not .... do it for all of them .