T4, Total details
Description
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.
Optimal & Reference range
T4, Total
µg/dL- Low
- Below optimal
- Optimal
- Above optimal
- High
- Optimal range
- 6 - 11.9
- Reference range
- 4.5 - 12
- Out of range
- <4.5 or >12
Interpretation
- Low: Your result is below the reference range. Discuss it with your healthcare provider, who can interpret it alongside your symptoms and other results.
- Below optimal: Your result is within the reference range, but below the range we consider optimal.
- Optimal: Your result is within the optimal range.
- Above optimal: Your result is within the reference range, but above the range we consider optimal.
- High: Your result is above the reference range. Discuss it with your healthcare provider, who can interpret it alongside your symptoms and other results.
- These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.
Blood tests with T4, Total
Explore available tests to better understand your results and gain deeper insights into your health.
Single marker
T4, Total
$7.99
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.
Panel
T4 (Thyroxine), Total
$5.99
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)
Thyroid Panel (T4 Total, T3 Uptake, T7)
$8.99
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)
Thyroid Panel with Thyroid-Stimulating Hormone (TSH)
$26.99
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)