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Free T3 (Triiodothyronine (T3), Free)


Free T3 (Triiodothyronine) – evaluate thyroid function and assess abnormal binding protein disorders.It measures serum triiodothyronine (T3) not bound to thyroid hormone-binding proteins (thyroid hormone-binding globulin [TBG], transthyretin, albumin). It is used, primarily in concert with measurement of thyroid-stimulating hormone (TSH) and free T4, in the diagnosis and management of hyperthyroidism and to clarify thyroid hormone status in the presence of a possible thyroid hormone-binding protein abnormality.

Synonyms: T3, Free; FT3

Specimen Required

SST. Volume 1 (0.5) mL serum. Stability: Refrigerated – 4 Days, Frozen – 2 Months

CPT Code(s)