Prothrombin Time PT
PT (Prothrombin Time) measures how long it takes blood to form a clot through the extrinsic and common coagulation pathways. It evaluates factors VII, X, V, II, and fibrinogen. PT is commonly reported alongside INR.
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PT (Prothrombin Time): what this test measures
This test measures the clotting time of plasma after adding tissue factor and calcium. The result is expressed in seconds. PT evaluates the extrinsic and common clotting pathways.
PT (Prothrombin Time): why this value matters
PT/INR is essential for warfarin monitoring, liver function assessment, and screening for clotting factor deficiencies.
PT (Prothrombin Time): how the blood test works
- Referral
- No GP referral needed. After the order we arrange the referral through ZorgDomein, within one business day; orders after 17:00 or at the weekend start on the next business day. ZorgDomein emails a barcode, and that barcode is what the draw site needs.
- The draw
- A blood draw from a vein in the arm, at a partner laboratory's draw site. No home kit, no finger prick.
- Which test
- on its own €13,-
- Where
- 650+ draw sites run by independent laboratories across the Netherlands. Draw sites
PT (Prothrombin Time): when is testing worthwhile?
PT is ordered before surgery, for warfarin monitoring, when liver disease is suspected, or when unexplained bleeding occurs. It is frequently ordered alongside aPTT.
PT (Prothrombin Time): symptoms of a high or low value
Low Levels
A short PT may suggest a hypercoagulable state, though it is rarely clinically significant in isolation.
High Levels
A prolonged PT may indicate liver disease, vitamin K deficiency, warfarin effect, or factor deficiency. Symptoms may include easy bruising and prolonged bleeding.
PT (Prothrombin Time): lifestyle and this value
Ensure adequate vitamin K intake through green leafy vegetables. If on warfarin, maintain consistent dietary habits and attend regular monitoring.
PT (Prothrombin Time): frequently asked questions
What is the difference between PT and INR?
PT is the raw measurement in seconds. INR normalises PT across laboratories using an international standard.
Can vitamin K deficiency affect PT?
Yes. Vitamin K is essential for producing factors II, VII, IX, and X. Deficiency prolongs PT.
Why is PT important for liver assessment?
The liver produces most clotting factors. PT reflects liver synthetic function and is included in MELD and Child-Pugh scores.
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Every result includes a professional assessment from a BIG-registered doctor. For treatment decisions, discuss your results with your GP.
PT (Prothrombin Time)
€13,-