warfarin (Coumadin, Panwarfin, Jantoven)

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Introduction

Tradenames: Coumadin, Panwarfin. (warfarin sodium)

* (see direct oral anticoagulant (DOAC) for safety vs warfarin)

Indications

Contraindications

Caution:

pregnancy category = x

safety in lactation = +

Benefit/risk

Dosage

* long-term low-intensity anticoagulation INR 1.5-2.0 (after 3 months of standard therapy) not recommended[54]

Tabs: 1, 2, 2.5, 5, 7, 10 mg.

Pharmacokinetics

elimination via liver

1/2life = 22-52 hours

protein binding = 99 %

Monitor

Adverse effects

Toxicity:

bleeding[13][14]

* Also see risk factors for persistently elevated INR

# vitamin K 2.5 mg PO as effective as 1 mg IV[12]; PO & IV more effective than SC[14];

* ref[27] suggests INR of 10 prior to vitamin K

* vitamin K reverses INR increase associated with warfarin overdose in a short time period - consider superwarfarin if reversal is prolonged[64]

Drug interactions

(also see prothrombin time)[10]

Laboratory

Mechanism of action

Management

More general terms

Additional terms

References

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