# warfarin

/wˈɔːfəɹˌɪn/ (UK) · CEFR C2 · Noun

Source: https://englishreference.com/word/warfarin
Updated: 2026-10-16

## Definition

a medicine that thins your blood so dangerous clots do not form. Doctors give it to people with heart problems or a high risk of stroke.

For teachers: an oral anticoagulant that blocks vitamin K-dependent clotting factors, prescribed to prevent thrombosis, embolism, and stroke in at-risk patients.

## Examples

- He takes warfarin every morning to thin his blood.
- After her heart valve surgery, the doctor prescribes warfarin and checks her blood regularly.
- Because warfarin interacts with leafy greens and many common drugs, patients on long-term therapy require frequent INR monitoring to keep clotting levels within a narrow safe range.

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