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Warfarin Dosing Nomogram
INR-based dose adjustment for anticoagulation management
Patient Parameters
Required (0.5–20)
Required (0.5–200)
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New Weekly Dose (mg)
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Avg Daily Dose (mg)
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Dose Change
| INR (target 2–3) | Action | Dose Adjustment |
|---|---|---|
| < 1.5 | Subtherapeutic | Increase weekly dose 15–20% |
| 1.5–1.9 | Below target | Increase weekly dose 5–10% |
| 2.0–3.0 | Therapeutic | No change |
| 3.1–3.5 | Supratherapeutic | Decrease weekly dose 5–10% |
| 3.6–4.0 | High | Hold 0–1 dose; decrease 10–15% |
| > 4.0 | Very high / Dangerous | Hold; reassess; vitamin K if indicated |
Reversal guidance: INR 4–10 (no bleeding): hold warfarin, recheck INR. INR >10 (no bleeding): vitamin K 2.5–5 mg PO. Any significant bleeding: 4-factor PCC + vitamin K 5–10 mg IV. Recheck INR 3–7 days after dose change.
