{"id":"total-t3","name":"Total T3 (Triiodothyronine)","shortName":"Total T3","aliases":["Total T3","T3, Total","Triiodothyronine, Total","Triiodothyronine (T3), Total","TT3","Total triiodothyronine","Triyodotironina total","Triiodothyronine (T3)","T3 Total","Serum T3"],"abbreviations":["TT3"],"loinc":[{"code":"3053-6","primary":true},{"code":"14930-2","primary":false}],"specimen":"serum-or-plasma","units":[{"ucum":"ng/dL","display":"ng/dL"},{"ucum":"nmol/L","display":"nmol/L"},{"ucum":"ng/mL","display":"ng/mL"}],"referenceRanges":[{"population":"11+","low":71,"high":180,"unit":"ng/dL","unitDisplay":"ng/dL","note":"Labcorp interval for people over 10 years (electrochemiluminescence immunoassay; Labcorp cites Roche's reference intervals). Only this one laboratory's intervals were confirmed, and other labs and methods, including mass spectrometry, print different limits, so use the range printed on your own report. Total T3 is about 50% higher in pregnancy, so this interval is not meant for pregnancy.","sources":[{"title":"Triiodothyronine (T3) (test 002188)","url":"https://www.labcorp.com/tests/002188/triiodothyronine-t3","publisher":"Labcorp"}]}],"review":{"status":"ai-draft","label":"AI-drafted. Awaiting verification","lastReviewed":"2026-10-03"},"summary":"Measures all the T3 in your blood, the more active thyroid hormone, including the part attached to carrier proteins.","url":"https://bloodtesttracker.com/markers/total-t3","notice":"Information, not medical advice. Ranges differ between labs, so the range on your own report is the one your result is judged against."}