Diagnostic test
T3 (Triiodothyronine)
About test
What does T3 (Triiodothyronine) measure?
The T3 (triiodothyronine) test measures the level of triiodothyronine, a thyroid hormone that helps regulate metabolism, energy use, heart rate, and body temperature. It may be ordered with other thyroid tests to help evaluate thyroid function, investigate symptoms that may be associated with an overactive or underactive thyroid, or monitor certain thyroid conditions. Results are interpreted alongside other thyroid hormone levels and clinical findings.
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.