Free T4 - Free thyroxine - serum

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Eurofins Biomnis code

FT4

Synonyms
  • Endocrinology
  • Free tetraiodothyronine
  • Free thyroxine
  • FT4
Specialty

Biochemistry


Clinical significance

The unbound, biologically active fraction of thyroxine (T4). Variations in the levels or affinity of transport proteins do not affect the level of the unbound form. High levels are associated with hyperthyroidism, thyroxine overload and amiodarone therapy. Low levels are associated with hypothyroidism and certain serious conditions not related to the thyroid gland.

Preanalytics
  • A tube specifically for this analysis : No
Further information

ATTENTION: interference possible in patients treated with biotin (vitamin B7, B8 or H) or taking any food supplement containing biotin. Essential to STOP treatment 8 days before taking the sample.


Methodology

Electrochemiluminescence

Turnaround time

1 day


Testing Laboratory

Biomnis Ivry