Kimberly
Online Facilitator
    Post count: 4288

    Hello – T4 has a “half-life” of approximately seven days. So the amount that is currently in your body includes half of what you took 7 days ago, 1/4 of what you took 14 days ago, 1/8 of what you took 28 days ago, etc..

    This slow build-up is why it takes a few weeks to fully see the results of any type of change (starting meds, changing dose, etc.) — so I can’t imagine you will see a *huge* difference in a day or two.

    However, if you have any concerns, definitely let your doctor know.

    Take care!