Anticoagulation Reversal Dose
Anticoagulation reversal dosing: 4F-PCC for warfarin (weight and INR driven) and idarucizumab for dabigatran, or protamine for unfractionated heparin.
Open the reference → Runs in your browser. Data leaves only if you deliberately send a problem report from the interactive tool.
Example
- Anticoagulant
- Warfarin (4F-PCC + Vit K)
- Weight
- 80 kg
- INR
- 5
Result: Warfarin, 80 kg, INR 5: 4F-PCC 35 units/kg = 2800 units + Vitamin K 5 to 10 mg by slow IV injection.
The tool opens with these values already filled in. Replace them with your own.
What you enter
- Anticoagulant
- Weight
- INR (required for warfarin; not read for the other agents)
- Heparin dose in last 2-3 h (units, UFH branch)
- Minutes since the last heparin dose (UFH branch, optional; adds the pediatric CHEST 2012 row)
What this is
Pull up the standard reversal options for the common anticoagulants on a single page - warfarin (vitamin K, four-factor PCC, fresh frozen plasma), dabigatran (idarucizumab), the direct factor-Xa inhibitors rivaroxaban / apixaban / edoxaban (andexanet alfa, four-factor PCC as an alternative), and the parenteral agents heparin (protamine) and enoxaparin (partial protamine reversal). Sophie Well lists the agent, the indication threshold, the typical dose, and the practical caveats (timing of the last anticoagulant dose, fibrinogen and platelet support, the cost and availability of the brand-name reversal agents).
When to use it
Use this when a patient on an anticoagulant presents with active major bleeding or needs an emergent procedure, when a covering provider is reviewing whether a recent intracranial hemorrhage warrants reversal versus expectant management, or when reviewing pharmacy stock before a high-risk procedure. The numbers here are reference values; the actual decision to reverse, which agent to use, and the supportive transfusion plan require attending and pharmacy input - the institutional protocol and current literature always supersede this table.
How this is calculated
Citation
Labels: 4F-PCC (Kcentra, Balfaxar) dosing by INR; idarucizumab 5 g; protamine 1 mg per 100 units, 50 mg maximum. Vitamin K and the pediatric protamine table: CHEST 2012. Andexanet: FDA safety communication, December 18, 2025. Frontera JA, et al. Neurocrit Care 2016;24(1):6-46. Read the sources: Kcentra label ↗, Balfaxar label ↗, Protamine label ↗, CHEST 2012 (adults) ↗, CHEST 2012 (children) ↗, Frontera 2016 ↗, FDA on Andexxa ↗
A reference and educational tool. Not medical, legal, or financial advice, and not a substitute for clinician judgment.
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