T3 - Overview: T3 (Triiodothyronine), Total, Serum

Test Catalog

Test Name

Test ID: T3    
T3 (Triiodothyronine), Total, Serum

Useful For Suggests clinical disorders or settings where the test may be helpful

Second-order testing for hyperthyroidism in patients with low thyroid-stimulating hormone values and normal thyroxine levels


Diagnosis of triiodothyronine toxicosis

Testing Algorithm Delineates situations when tests are added to the initial order. This includes reflex and additional tests.

See Thyroid Function Ordering Algorithm in Special Instructions.

Special Instructions and Forms Library of PDFs including pertinent information and consent forms, specimen collection and preparation information, test algorithms, and other information pertinent to test

Method Name A short description of the method used to perform the test

Electrochemiluminescence Immunoassay

NY State Approved Indicates the status of NY State approval and if the test is orderable for NY State clients.


Reporting Name A shorter or abbreviated version of the Published Name for a test; an abbreviated test name

T3 (Triiodothyronine), Total, S

Aliases Lists additional common names for a test, as an aid in searching

T3 Suppression
T3 Total, Serum
Total T3, Serum
Triiodothyronine (T3)
Triiodothyronine, Total T3
T3 (Triiodothyronine), Total Only, Serum (Order T3 unless specified)
Thyroid Function Cascade
Triiodothyronine (Order T3 if not specified)