IWPC pharmacogenetic warfarin dose

IWPC pharmacogenetic warfarin dose (Klein, NEJM 2009): a published linear model predicting the stable weekly maintenance dose from age, height, weight, race, enzyme-inducer and amiodarone use, and the VKORC1 / CYP2C9 genotypes.

Open the calculator → Runs in your browser. Data leaves only if you deliberately send a problem report from the interactive tool.

Example

Age
65 years
Height
170 cm
Weight
70 kg
VKORC1 (-1639 G>A) genotype
G/G
CYP2C9 genotype
*1/*1
Race / ethnicity
White / Caucasian
Enzyme inducer
No
Amiodarone
No

Result: IWPC predicted maintenance dose 41.1 mg/week

The tool opens with these values already filled in. Replace them with your own.

What you enter

  • Age
  • Height
  • Weight
  • VKORC1 (-1639 G>A) genotype
  • CYP2C9 genotype
  • Race / ethnicity
  • Enzyme inducer (carbamazepine, phenytoin, rifampin)
  • Amiodarone
How this is calculated

International Warfarin Pharmacogenetics Consortium; Klein TE, Altman RB, Eriksson N, et al. Estimation of the warfarin dose with clinical and pharmacogenetic data. N Engl J Med. 2009;360(8):753-764. Read the source ↗

A reference and educational tool. Not medical, legal, or financial advice, and not a substitute for clinician judgment.

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Built by Clay Good. Source on GitHub.