{"id":"inr","name":"INR (International Normalized Ratio)","shortName":"INR","aliases":["INR (Thromborel-S)","INR","International Normalized Ratio","INR (PT)","INR, Plasma","INR Value","International normalised ratio","INR (Prothrombin Time)","INR, Point of Care","INR Finger Stick"],"abbreviations":["INR"],"loinc":[{"code":"6301-6","primary":true},{"code":"34714-6","primary":false},{"code":"46418-0","primary":false},{"code":"38875-1","primary":false}],"specimen":"plasma","units":[{"ucum":"{INR}","display":"INR"}],"referenceRanges":[{"population":"Adults","low":0.9,"high":1.1,"unit":"{INR}","unitDisplay":"INR","note":"Interval from Mayo Clinic Laboratories for people who are not taking warfarin (0.9–1.1); ARUP publishes only the warfarin ranges. Limits vary a little by lab and reagent, so use the range on your report. If you take warfarin, a higher INR is intended and your clinician sets your own target. Mayo and ARUP both describe 2.0–3.0 as the standard-intensity warfarin range and 2.5–3.5 as the high-intensity range. Diet (for example leafy greens high in vitamin K), alcohol, other medicines and supplements can all change the INR.","sources":[{"title":"Prothrombin Time, Plasma (test PTTP), including INR","url":"https://www.testcatalog.org/show/PTTP","publisher":"Mayo Clinic Laboratories (Extended Catalog)"},{"title":"Prothrombin Time/International Normalized Ratio (ARUP test 0030224)","url":"https://ltd.aruplab.com/Tests/Pub/0030224","publisher":"ARUP Laboratories"},{"title":"Prothrombin Time Test and INR (PT/INR)","url":"https://medlineplus.gov/lab-tests/prothrombin-time-test-and-inr-ptinr/","publisher":"MedlinePlus (National Library of Medicine)"}]}],"review":{"status":"ai-draft","label":"AI-drafted. Awaiting verification","lastReviewed":"2026-10-03"},"summary":"A standard way to report how long your blood takes to clot, used mainly to monitor warfarin and to check clotting and liver function.","url":"https://bloodtesttracker.com/markers/inr","notice":"Information, not medical advice. Ranges differ between labs, so the range on your own report is the one your result is judged against."}