Vitamin K antagonists
Drug Safety Update
June 2024: Warfarin: be alert to the risk of drug interactions with tramadol
October 2020: Warfarin and other anticoagulants: monitoring of patients during the COVID-19 pandemic
September 2017: Miconazole (Daktarin): over-the-counter oral gel contraindicated in patients taking warfarin
January 2017: Direct-acting antivirals to treat chronic hepatitis C: risk of interaction with vitamin K antagonists and changes in INR
July 2016: Warfarin: reports of calciphylaxis
NICE Guidance
NG158: Venous thromboembolic diseases: diagnosis, management and thrombophilia testing
NG128: Stroke and transient ischaemic attack in over 16s: diagnosis and initial management
NG196: Atrial fibrillation: diagnosis & management, June 2021
Warfarin dose is adjusted according to the international normalised ratio (INR). Target INR should be clearly identified at initiation of therapy and depends on the indication.
Indication and duration of treatment should be clearly recorded at initiation of treatment in the patient-held anticoagulant treatment booklet "yellow book".
Pregnancy: warfarin must not be used, LMWHs are the treatment of choice during pregnancy.
Drug interactions: many drugs interact with warfarin. If a new drug is started for a patient stabilised on warfarin check for an interaction. INR may need to be monitored more frequently.
See here for MTW guidance for adult patients on warfarin.
| Pack |
|---|
| 28 tablet |
| Pack |
|---|
| 28 tablet |
| 100 tablet |
| 500 tablet |
| Pack |
|---|
| 28 tablet |
| 100 tablet |
| 500 tablet |
| Pack |
|---|
| 28 tablet |
| 100 tablet |
| 500 tablet |
| Pack |
|---|
| 28 tablet |
| 100 tablet |
| Pack |
|---|
| 28 tablet |
| 100 tablet |
- On Formulary Preferred
- On Formulary Second Line
- On Formulary Third Line
- Specialist Initiation
- Secondary Care Only
- Not Approved for Formulary