Thyroid Panel (TSH, Free T3, Free T4)
TSH, Free T3, and Free T4 — a complete thyroid function workup.
What this test measures
Evaluates thyroid function with TSH (the pituitary signal), Free T3 (active hormone), and Free T4 (storage hormone) for screening hypothyroidism and hyperthyroidism.
Who should take this test
Anyone with fatigue, unexplained weight changes, hair loss, cold/heat intolerance, or family history of thyroid disease.
Biomarkers included
Preparation
No fasting required. Take biotin supplements at least 72 hours before to avoid interference.
How it works
- 01. Order online — physician order included.
- 02. Visit a CLIA-certified draw site near you.
- 03. Get results in 1–3 business days via secure portal.
Find a lab near you
Use our partner's 4,500+ CLIA-certified Quest and LabCorp draw sites nationwide.
Search by ZIPFrequently asked questions
Will biotin affect results?
Yes — stop biotin 72 hours prior.
Should I test in the morning?
Morning testing is preferred for the most consistent TSH readings.
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Medical disclaimer: This test is for informational and screening purposes only and is not a substitute for medical advice, diagnosis, or treatment. Results should be reviewed with a qualified healthcare provider.