Key points

  • We recommend to consult your poison centre with the use of this antidote.
  • Do not give vitamin K prophylactically if the INR is normal.
  • Risk of bleeding is higher if INR is greater than 5 and also in elderly or hypertensive patients.
  • Onset of action on INR: Warfarin, 8 to 12 hrs; "Superwarfarin" 48-72 hrs.
  • Rodenticides containing "Superwarfarin" such as brodifacoum can cause anticoagulation lasting several months.
  • Oral route is preferred when it appears there is no immediate risk of bleeding. The SC route is not recommended due to erratic absorption. IM is generally not recommended due to risk of hematoma; some prefer to avoid IV because of the risk of a severe reaction (e.g. anaphylaxis, shock, cardiac arrest) even during slow IV infusion.

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Last updated : 2022-12-12