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The Anticoagulant service closely monitors the use of blood thinners to prevent blood clots forming, reducing the likelihood of conditions such as strokes or heart attacks.

As part of the Haematology team we test and measure the effect of blood thinners, such as warfarin or sinthrome, and use a blood sample from a patient to advise on the correct dosage.

What we do

  • Allow safe and effective use of the Vitamin K antagonists (VKAs),which are more commonly known as blood thinners.
  • Your dosage is adjusted using an INR test.
  • The service is clinically led by a Consultant Haematologist and managed by Specialist Biomedical Scientists working with Pathology.
  • There are nurse-led anticoagulant clinics. 


What happens if you are referred to this service?

You will receive a letter asking you to attend an appointment for a blood test, which could be at Princess Alexandra Hospital, St Margaret's Hospital, Herts and Essex Hospital or your local GP surgery.

Following the blood test your sample will be taken to the lab and a letter will be sent to you advising you what dose you need. You may also be contacted by telephone depending on the circumstances.

In some cases, District Nurses will arrange for you to attend PAH for Vitamin K if your INR is too high and arrange prescriptions and a supply of Enoxaparin when required.