MedFast.AI

Clotting

INR

Also known as: Prothrombin Time Ratio, PT-INR

What it means

Measures how quickly your blood clots. Patients on blood-thinners (Warfarin/Acitrom) monitor this monthly. Higher = thinner blood.

Typical normal range

Off medication: 0.8–1.1 · On Warfarin: 2.0–3.0

Reference ranges vary by lab, age, sex, and pregnancy. Always check the range on your own report.

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Related terms in Clotting

Sources & Standards

The plain-language explanations above draw on published standards from the following bodies. Reference ranges and thresholds vary slightly by lab and demographic — always check the range on your own report and follow your doctor's interpretation.

AI can be wrong. Explanations here are for comprehension only — confirm every decision with your doctor.

This is a plain-language explanation for patients, not clinical advice. AI can be wrong. Always confirm with your doctor.