Purpose:
To ensure the safe, effective, and compliant storage and administration of Warfarin, a high-risk anticoagulant used to prevent blood clots.
Audience:
This article is intended for live-in carers at edyn.care.
❓ What is Warfarin and What Is It Used For?
Warfarin is a prescription anticoagulant (commonly known as a “blood thinner”). It reduces the blood's ability to form clots, helping to prevent serious medical conditions caused by unwanted clots in the blood vessels.
🔹 Conditions Warfarin is Prescribed For:
Atrial fibrillation (AF) – to reduce the risk of stroke.
Deep vein thrombosis (DVT) – to prevent or treat blood clots in the legs.
Pulmonary embolism (PE) – to treat blood clots in the lungs.
Heart valve replacement – to prevent clot formation on artificial valves.
Thrombophilia – for people with an increased tendency to form blood clots.
Warfarin does not dissolve existing clots but prevents new ones from forming or existing clots from growing.
Caution:
Because it affects the blood’s clotting ability, incorrect doses can lead to serious bleeding or clotting events. Therefore, close monitoring through regular blood tests (INR) is essential.
🔐 Safe Storage of Warfarin
✅ Storage Guidelines
Location: Store in a locked medication cabinet or secure storage as per the service user's care plan.
Temperature: Keep at room temperature (below 25°C). Do not refrigerate.
Container: Keep in the original packaging with the pharmacy label clearly visible.
Separation: Store away from food, drinks, and non-medicinal substances.
Access: Only authorised personnel should have access.
💊 Administration Procedure
Warfarin dosing is highly individualised and based on regular blood tests (INR - International Normalised Ratio). Follow these steps carefully.
1. Preparation
Wash your hands, wear appropriate PPE and ensure a clean environment.
Check the Medication Administration Record (MAR) chart.
Confirm the following:
Right person
Right medicine
Right dose (based on latest INR result)
Right time
Right route (oral)
2. Checking the INR Result
Warfarin must not be administered unless a valid INR result and corresponding dose are confirmed.
🔍 How to Check the INR Result
Review the yellow INR slip for documented INR values and prescribed doses.
Look for the latest entry such as:
🗓️ INR: 2.5 on 10/06/25 - 24/06/25 | 💊 Dose: 3mg daily
If the result is outdated or missing, contact the GP, district nurse, or anticoagulation clinic.
🧾 Acceptable INR Sources:
Yellow Warfarin dosing booklet
Anticoagulation clinic letters
GP surgery phone call (record the name and time)
Electronic records (EMIS or similar)
Never administer Warfarin based on guesswork or historic doses.
3. Administration
Provide the Warfarin orally with water. Do not crush or alter unless explicitly prescribed.
Stay with the individual to confirm it has been swallowed.
Immediately document the administration on the MAR chart.
Note the dose given, time, and any side observations (e.g., bruising, bleeding risk).
If antibiotics are prescribed to be administered, notify the Warfain nurses before administering, as these will impact the INR reading and subsequent prescribed Warfarin doses.
📝 How to Record an INR Result
If you receive or are asked to record a new INR result, follow this process:
Step-by-Step:
Receive the Result
From GP, nurse, clinic, or via documentation. You will never be asked to conduct an INR reading yourself. It needs to be completed by a qualified Warfarin nurse.
Record in the Following Locations:
Daily care notes
Time of INR reading and name of the Nurse
INR reading (e.g., 2.3)
Any concerns and/or notes of conversations had
Communication Log (digital or written)
Yellow Warfarin Booklet (if used in home)
Example Entry:
10/06/2025: INR 2.3. Dose: 3mg daily. Next test: 17/06/25. Per Dr Smith (GP).
Initial and Date all entries clearly.
Escalate If:
INR is dangerously high (>4.0) or low (<1.5)
You are unsure of the instructions
An INR result is overdue
📋 Monitoring and Documentation
Ensure you have read and understood the Warfarin Risk Assessment in your client’s care plan, and review it when updates are announced by the Care Manager
Always use the MAR chart and update it promptly.
Record any missed/refused doses, with reasons, and inform the office straight away.
Watch for signs of excessive bleeding, bruising, or confusion.
Never pre-fill a Warfarin chart, as the doses are subject to frequent change
⚠️ Special Considerations
Warfarin interacts with many common foods and medications, such as antibiotics.
Encourage a consistent diet; report new supplements or medications.
Ensure communication with the care team when results or doses change.
📞 Emergency Protocol
If you suspect overdose or abnormal bleeding:
Call 999 immediately.
Notify the registered manager or on-call staff member.
Complete an incident report and record in the care notes.