Prothrombin time (PT) is a blood test that measures the time it takes for the liquid portion (plasma) of your blood to clot. A prothrombin time test can be used to check for bleeding problems. PT is also used to check whether medicine to prevent blood clots is working. A PT test may also be called an INR test. INR stands for 'international normalized ratio'.
The INR is typically used to monitor patients on warfarin or related oral anticoagulant therapy. The normal range for a healthy person not using warfarin is 0.8–1.2, and for people on warfarin therapy an INR of 2.0–3.0 is usually targeted, although the target INR may be higher in particular situations, such as for those with a mechanical heart valve. If the INR is outside the target range, a high INR indicates a higher risk of bleeding, while a low INR suggests a higher risk of developing a clot.
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14.3.3 ETA PROTEIN, Acetylcholine Receptor (AChR) Antibody, Activated partial thromboplastin time (APTT), Alpha 2-Macroglobulins, Qn, ANA SCREEN, IFA, ANA titer, Anti-DBL-Strand DNA Ab, Anti-Smith Antibody, Anticardiolipin Ab, IgM, Anticardiolipin Ab,IgA,Qn, Anticardiolipin Ab,IgG,Qn, Antinuclear Antibodies Direct (ANA Direct), Antiphosphatidylserine IgA, Antiphosphatidylserine IgG, Antiphosphatidylserine IgM, C1 Esterase Inhibitor, Func, C1 Esterase Inhibitor, Serum, C3A Desarg Fragment, CARDIOLIPIN AB (IGA), CARDIOLIPIN AB (IGG), CARDIOLIPIN AB (IGM), CCP Antibodies IgG/IgA, Complement C3, Complement C3a, Complement C4, Serum, Complement C4a, Complement, Total (CH50), Complement, Total (CH50) / Quest, Cyclic Citrullinated Peptide Antibody, Dilute Russell's viper venom time (dRVVT), DRVVT SCREEN, ds-DNA Antibody, IgG, Erythrocyte Sedimentation Rate (ESR), Free Kappa Lt Chains, Serum, Free Lambda Lt Chains, Serum, Gastrin, Histamine, Plasma, HLA-B27 (Human Leukocyte Antigen B27), Immature Grans (Abs), Immature Granulocytes (%), Immunofixation Result, Serum, Immunoglobulin A, Qn, Serum, Immunoglobulin D, Quant, Serum, Immunoglobulin E, Total, Immunoglobulin G, Qn, Serum, Immunoglobulin M, Qn, Serum, Interleukin-2, Serum, Interleukin-6, Jo 1 Antibodies, IgG, Serum, Kappa/Lambda Ratio, Serum, Liver-Kidney Microsomal Antibodies, Lupus Anticoagulant, PHOSPHATIDYLETHANOLAMINE AB (IGA), PHOSPHATIDYLETHANOLAMINE AB (IGG), PHOSPHATIDYLETHANOLAMINE AB (IGM), PHOSPHATIDYLSERINE AB (IGA), PHOSPHATIDYLSERINE AB (IGG), PHOSPHATIDYLSERINE AB (IGM), Plasminogen Activator Inhibitor (PAI-1) AG, Prothrombin Fragment 1.2, Prothrombin Time (PT), Prothrombin Time (PT) INR, RA Latex Turbid, Reptilase Clotting Time, Rheumatoid factor, TGF-b1, Thrombin time, Thrombin-Antithrombin TAT, Transforming Growth Factor beta, Plasma, Tryptase, VEGF, Plasma