US Medical Term · tests
Prothrombin Time / INR (PT/INR)
Tiempo de protrombina / INR
In 9 languages
| Language | Term |
|---|---|
| English | Prothrombin Time / INR (PT/INR) |
| Spanish (Español) | Tiempo de protrombina / INR |
| Chinese (中文) | 凝血酶原時間／INR |
| Korean (한국어) | 프로트롬빈 시간 / INR |
| Vietnamese (Tiếng Việt) | Xét nghiệm thời gian prothrombin / INR |
| Filipino (Tagalog) | Prothrombin Time / INR |
| Portuguese (Português) | Tempo de protrombina / INR |
| Thai (ภาษาไทย) | การตรวจเวลาโปรทรอมบิน / INR |
| Japanese (日本語) | プロトロンビン時間／INR |
What it means
The prothrombin time (PT) test measures how long it takes your blood to clot. The international normalized ratio (INR) converts that time into a standardized number so results can be compared across different laboratories. A blood sample is drawn from a vein in your arm. For most healthy adults, the INR is around 1.0. People taking blood-thinning medication (warfarin/Coumadin) are monitored regularly and typically kept in a therapeutic range of 2.0–3.0, depending on their condition. Doctors use PT/INR before surgery, to diagnose clotting disorders, to assess liver function (since the liver makes clotting proteins), and to monitor anticoagulant therapy.
How to say it
Sentences a patient might use with a doctor, nurse, pharmacist, or insurer:
Why does my doctor check my INR so often since I started taking warfarin?
¿Por qué mi médico revisa mi INR con tanta frecuencia desde que empecé con warfarina?
My INR is too high — does that mean I am bleeding too easily?
Mi INR está demasiado alto — ¿eso significa que sangro con demasiada facilidad?
Should I take my blood thinner the morning of my PT/INR blood draw?
¿Debo tomar mi anticoagulante la mañana de la extracción de sangre para el PT/INR?
Where you'll see it
Related terms
Sources
Last reviewed: September 2026