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Thyroid

Free T4

Also written as Free thyroxine.

Core panel — run every month

What it indicates

The unbound form of the main hormone the thyroid releases.

Why a series helps

It is steadier than TSH, so following the two together shows more than either one alone.

What this page does not tell you

What a particular Free T4 result means depends on you: your history, your medication, why the test was taken. Ziro does not interpret results for individuals and does not diagnose. If something in your results warrants a conversation, that conversation is with a doctor, and your results are downloadable so you can bring them.

Others in thyroid

The hormones that set the pace of your metabolism.