Diagnostic test
Trilodothyronine - Free (FT3)
About test
What does Trilodothyronine - Free (FT3) measure?
The Free Triiodothyronine (FT3) test measures the unbound, active form of the thyroid hormone triiodothyronine in the blood. FT3 helps assess thyroid hormone activity and may be used along with other thyroid tests, such as TSH and free T4, when evaluating symptoms or conditions related to an overactive or underactive thyroid. Results are interpreted in the context of other test findings and clinical information.
This overview is educational. Use the recorded preparation, sample and lab-partner details below for collection guidance, and confirm any missing information before collection.
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Prices, report times and availability are shown from the catalog records for each eligible partner.
Sagepath Labs
- Sample for analysis
- Serum (1 mL)
- Report time
- 11:00/18:00
Preparation and specimen requirements can vary by test and laboratory. Follow the instructions shown for your selected partner and any advice from your healthcare professional.