Interpret Your Activated Partial Thromboplastin Time Results
Enter your aPTT 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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Activated Partial Thromboplastin Time Normal Ranges
aPTT measures the time for blood to clot via the intrinsic coagulation pathway, which includes factors XII, XI, IX, VIII, X, V, II, and I.
| Reference Range | Unit | Notes |
|---|---|---|
| 25 – 38 | seconds | Normal (not on heparin) |
| 60 – 100 | seconds | Therapeutic range on UFH |
Critical (Panic) Values
Critical High: > 120 seconds. Values outside these limits require immediate clinical attention.
Common Causes of High aPTT
Common Causes of Low aPTT
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