Test Overview
Test Methodology

Chemiluminescent Immunoassay

Test Usage

Evaluating biochemical status of clinically euthyroid patients; further confirmatory test for hyperthyroidism monitoring thyroid replacement therapy.

Reference Range *

1.9 - 3.9 pg/mL

* Reference ranges may change over time. Please refer to the original patient report when evaluating results.

Test Limitations

Specimen may be stored at room temperature up to 8 hours. [12/05]

Test Details
Days Set Up
Daily, 24 hours
Analytic Time

4 hours

Soft Order Code
FT3
MiChart Code
T3, Free
Synonyms
  • Free T3
  • Free T3 (Triiodothyronine)
  • FT3
  • T3 Triiodothyronine Free Serum
  • Triiodothyronine
  • Triiodothyronine, Free
Laboratory
Chemical Pathology
Section
Automation
Specimen Requirements
Collection Instructions

Collect specimen in a red top or SST tube. Centrifuge, aliquot serum into a plastic vial and refrigerate up to 48 hours or freeze for longer storage.

Alternate Specimen
Red Top Tube
Rejection Criteria
Anticoagulants not acceptable.
Yellow Top Tube
Normal Volume
0.5 mL serum
Minimum Volume
0.25 mL serum
Billing
CPT Code
84481
Fee Code
32013
LOINC
3051-0
Resources