T4, Total details
What T4, Total shows
Total T4 measures thyroxine (T4), your main thyroid hormone, including both the protein-bound (inactive) and unbound (active) portions together. Because total T4 can be affected by changes in binding protein levels (which shift with pregnancy, liver disease, certain medications like estrogen, or genetic variation), free T4 is generally considered a more reliable and commonly used measurement today, though total T4 is still used in some contexts, sometimes alongside T3 uptake to calculate the Free Thyroxine Index.
Normal ranges
Typical adult range
4.5–12 µg/dL
Most labs report a range close to this
Hormunity optimal range
6–11.9 µg/dL
A narrower functional target
Each lab sets its own reference range. Always compare your result with the range printed on your report, and review it with a healthcare provider.
Tests that include T4, Total
T4, Total measures the overall amount of thyroxine in the blood, including both bound and unbound forms. It is used to assess thyroid function and can help diagnose conditions such as hypothyroidism or hyperthyroidism.
- T4, Total Measures total thyroxine (T4), including both bound and unbound hormone, used in thyroid function evaluation.
For diagnosis of hypothyroidism and hyperthyroidism.
- T3 Uptake An older test used, together with total T4, to estimate free thyroid hormone levels by assessing binding protein capacity.
- T4, Total Measures total thyroxine (T4), including both bound and unbound hormone, used in thyroid function evaluation.
- Free T4 Index (T7) Free Thyroxine Index — a calculated estimate of free T4 thyroid hormone, adjusting total T4 for binding protein levels.
The Thyroid Panel assesses 4 key markers related to thyroid function. It helps evaluate overall thyroid health and is commonly used to diagnose conditions like hypothyroidism, hyperthyroidism, and monitor thyroid therapy.
- T3 Uptake An older test used, together with total T4, to estimate free thyroid hormone levels by assessing binding protein capacity.
- T4, Total Measures total thyroxine (T4), including both bound and unbound hormone, used in thyroid function evaluation.
- Thyroid-Stimulating Hormone (TSH) A pituitary hormone that signals your thyroid to produce hormone. The primary screening test for both underactive and overactive thyroid conditions.
- Free T4 Index (T7) Free Thyroxine Index — a calculated estimate of free T4 thyroid hormone, adjusting total T4 for binding protein levels.
The Thyroid Panel assesses 4 key markers related to thyroid function. It helps evaluate overall thyroid health and is commonly used to diagnose conditions like hypothyroidism, hyperthyroidism, and monitor thyroid therapy.
- T3 Uptake An older test used, together with total T4, to estimate free thyroid hormone levels by assessing binding protein capacity.
- T4, Total Measures total thyroxine (T4), including both bound and unbound hormone, used in thyroid function evaluation.
- Thyroid-Stimulating Hormone (TSH) A pituitary hormone that signals your thyroid to produce hormone. The primary screening test for both underactive and overactive thyroid conditions.
- Free T4 Index (T7) Free Thyroxine Index — a calculated estimate of free T4 thyroid hormone, adjusting total T4 for binding protein levels.
This test is crucial for diagnosing thyroid conditions such as hypothyroidism (underactive thyroid) and hyperthyroidism (overactive thyroid). By measuring the total level of thyroxine (T4) in the blood, it helps in understanding thyroid function and identifying potential issues.
- T4, Total Measures total thyroxine (T4), including both bound and unbound hormone, used in thyroid function evaluation.
- Free T4 Index (T7) Free Thyroxine Index — a calculated estimate of free T4 thyroid hormone, adjusting total T4 for binding protein levels.
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