Interpret Your Prothrombin Time / INR Results
Enter your PT/INR value below and get an instant, free AI interpretation — a plain-English explanation checked against WHO/IFCC reference ranges.
Medical Disclaimer
This AI-generated interpretation is for educational purposes only and does not constitute medical advice, diagnosis, or treatment. Results may vary based on individual health factors not captured here.
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Prothrombin Time / INR Normal Ranges
Prothrombin time (PT) measures how long it takes blood to clot via the extrinsic coagulation pathway, which includes factors I, II, V, VII, and X.
| Reference Range | Unit | Notes |
|---|---|---|
| 11 – 13.5 | seconds | Prothrombin Time (PT) |
Also reported in: INR.
Critical (Panic) Values
Critical High: > 5 seconds. Values outside these limits require immediate clinical attention.
Common Causes of High PT/INR
Common Causes of Low PT/INR
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