Thyroxine
0070140
Ordering Recommendation
Not recommended for routine thyroid screening.
Mnemonic
T4
Methodology
Quantitative Electrochemiluminescent Immunoassay
Performed
Sun-Sat
Reported
Within 24 hours  
New York DOH Approval Status
This test is New York DOH approved.
Submit With Order
Specimen Required
Patient Preparation
  
Collect
Serum separator tube or plasma separator tube. Also acceptable: Lavender (EDTA).  
Specimen Preparation
Allow specimen to clot completely at room temperature. Separate serum or plasma from cells ASAP or within 2 hours of collection. Transfer 1 mL serum or plasma to an ARUP Standard Transport Tube. (Min: 0.5 mL)  
Storage/Transport Temperature
Refrigerated.  
Unacceptable Conditions
Grossly hemolyzed specimens.  
Remarks
  
Stability
After separation from cells: Ambient: 24 hours; Refrigerated: 1 week; Frozen: 1 month  
Reference Interval
 
 
Cord blood 6.60-​17.50 µg/dL
0-​3 days 5.37-​22.40 µg/dL
4-​30 days 5.24-​23.20 µg/dL
1-​23 months 5.37-​16.00 µg/dL
2-​6 years 5.26-​14.80 µg/dL
7-​11 years 5.70-​14.10 µg/dL
12-​19 years 4.74-​14.60 µg/dL
20 years and older 5.10-​14.10 µg/dL
Interpretive Data
 
Note
 
CPT Code(s)
84436
Components
Component Test Code*Component Chart NameLOINC
0070140Thyroxine3026-2
* Component test codes cannot be used to order tests. The information provided here is not sufficient for interface builds; for a complete test mix, please click the sidebar link to access the Interface Map.
Aliases
  • Syn-Thyroid
  • T4
  • T4 Total Only, T4, Serum
  • Tetraiodothyronine
  • Thyroid Hormone
  • Thyroxine (T4)
  • Total T4