Timing of T3 & T4 for blood test: I am about to... - Thyroid UK

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Timing of T3 & T4 for blood test

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I am about to do a blood test. I normally take T3 at 8am and 8pm and T4 at 8am. I am hoping to do blood test at 8am, so should I take the previous eve dose of T3 at 9pm and the morning dose of T3 and T4 after the blood test, please? Just want to be sure I get this right. Thanks 😊

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SeasideSusie profile image
SeasideSusieRemembering

It will be fine to take your last dose of T3 anywhere between 8pm and midnight the night before, the time gap should be 8-12 hours.

Take your last dose of Levo at 8am as normal the day before the test.

After the test, take that day's Levo and first dose of T3.

Agapanthus1 profile image
Agapanthus1 in reply to SeasideSusie

Brill! Thanks so much πŸ’πŸ˜Š

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