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Anticoagulation - oral - Management
How long is warfarin prescribed for?

  • For people with deep vein thrombosis (DVT) and pulmonary embolism:
    • Duration of treatment for deep vein thrombosis (DVT) will vary for each individual, depending on a variety of factors. Experts are not unanimous on the optimal duration of warfarin treatment, but usually it should be continued for at least:
      • Six weeks in people with distal DVT (calf vein thrombosis).
      • Three months in people with proximal DVT or pulmonary embolism where there are known temporary risk factors and there is considered to be a low risk of recurrence.
      • Six months in people with proximal DVT due to an unknown cause (idiopathic).
      • Long-term if there have been recurrent DVTs or pulmonary embolism.
    • Warfarin can be stopped abruptly without harm when the duration of treatment is completed.
  • For people with atrial fibrillation (AF):
    • Warfarin treatment is usually long-term.
    • If the person is going to have cardioversion, treatment with warfarin is usually 3 weeks before and 4 weeks after (if normal sinus rhythm is maintained).
    • People who have undergone cardioversion and have a high risk of AF recurring also require long-term warfarin therapy. People at high risk of AF recurring include those with:
      • A history of failed attempts at cardioversion.
      • Structural heart disease (mitral valve disease, left ventricular dysfunction or an enlarged left atrium).
      • A prolonged history of AF (greater than 12 months).
      • Previous recurrences of AF.
  • For people with mechanical prosthetic heart valves warfarin treatment is usually long-term.

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