Warning

Background

INR is a specific measure of the level of anticoagulation from coumarin therapy (most common drug being Warfarin).

When to test

  • When monitoring coumarin therapy.
  • Secondary care may use as part of prognostic scores for liver damage.

When not to test

Outside of coumarin monitoring an INR should not be checked.

When to repeat a test

As part of coumarin therapy monitoring.

Download summary

A PDF summary document is available here.

Editorial Information

Last reviewed: 03/10/2023

Next review date: 03/10/2024

Version: 1

Approved By: National Demand Optimisation Group - Education Short Life Working Group