Synonyms: Triiodothyroxine; Total T3
Computer Code: (T3X)
Specimen Collection: 3 mL blood (light green top (Li Heparin) preferred. Red/gold acceptable). This test may exhibit interference when sample is collected from a person who is consuming a supplement with a high dose of biotin (also termed as vitamin B7, vitamin H, or coenzyme R). It is recommended to ask all patients who may be indicated for this test about biotin supplementation. Patients should be cautioned to stop biotin consumption at least 72 hours prior to the collection of a sample.
Minimum Volume: 1 mL
Handling Instructions for Offsite Areas: If red or gold top, allow to clot. All tube types should be centrifuged for 20 minutes and refrigerated. Serum must be removed from red top tube. Min 0.5 mL serum/plasma.
Reference Values: >18 years: 79-149 NG/DL
Lab Code: CC
Requisition: SPEC C
Test Frequency: Daily
Routine TAT: 4 hrs
Stat TAT: 60 min
CPT Code(s): 84480
Methodology Used:
See Addendum XVII