Thyroid Function
T4 (Thyroxine)
T4 is the primary hormone secreted by your thyroid gland. Your body converts T4 into T3, the active form, to regulate your metabolism.
Why is it tested?
To evaluate thyroid function, diagnose thyroid diseases, and monitor treatment.
What does a HIGH level mean?
- Hyperthyroidism
- Graves' disease
- Thyroiditis (early stages)
What does a LOW level mean?
- Hypothyroidism
- Hashimoto's thyroiditis
- Iodine deficiency
- Pituitary gland issues
Normal Reference Range
4.6 to 11.2 mcg/dL (Total T4)
*Ranges may vary slightly depending on the specific laboratory and testing methods used.
Related Biomarkers
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