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Thyroid Panel Suiteblood

Free T4

Alternative names: FT4, Free Thyroxine, Thyroxine Free

Clinical Summary

MedlinePlus describes T4 as thyroxine, one of the main hormones produced by the thyroid gland to control metabolism.

Higher-Than-Range Notes

MedlinePlus notes high Free T4 levels suggest an overactive thyroid gland (hyperthyroidism).

Lower-Than-Range Notes

MedlinePlus notes low Free T4 levels suggest an underactive thyroid gland (hypothyroidism).

Commonly Measured Alongside

Longitudinal Tracking

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General Reference Information: This definition is sourced from public health reference libraries for patient education. It is not intended to substitute professional medical diagnosis, clinical reviews, or treatment plans. Always consult with a qualified health provider regarding your laboratory results.