# Blood work after change in dosage



## DB22 (Apr 26, 2015)

When do you see a change in the blood work after changing dosage from 100 to 50 mg of levothyroxine?

The half life is 2 weeks I've heard. Does it mean it takes 2 weeks for the blood work to result in 50% change in the thyroid hormones?


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## Lovlkn (Dec 20, 2009)

Not sure what the 1/2 life is, but I can tell you that 6 weeks is the "normal" amount of time to see what the results of a medication dosage change is .

Why such a large dose reduction? Do you have any labs with ranges at the 100mcg dosage?


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## Andros (Aug 26, 2009)

Half-life of T4 is 8 weeks; half-life of T3 is 3 days.

What is your diagnosis? What tests have you had?

Welcome!


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