Total Triiodothyronine (Total T3)
Hormone markersWhat the test generally measures, and what to ask about it.
Longetic keeps every lab and record you’ve had organized and easy to find, so your own Total Triiodothyronine (Total T3) values sit together on one chart and you walk into your next appointment prepared.
What is Total Triiodothyronine (Total T3)?
Measures all of the active thyroid hormone triiodothyronine in your blood, both the free portion and the part bound to proteins.
Triiodothyronine, or T3, is one of the main thyroid hormones that set the pace of your metabolism, and the total T3 test measures the free and protein-bound amounts together. Higher levels can be associated with an overactive thyroid, while lower levels can be associated with an underactive thyroid or with non-thyroid illness. T3 is usually checked as part of a broader thyroid panel with TSH and T4 rather than on its own.
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