medication

Warfarin (Coumadin)

Also known as: Coumadin

Half-life
40 h
Typical timing
evening
Food rule
either
Default unit
mg

Overview

Warfarin, commonly known by its brand name Coumadin, is an anticoagulant medication. It functions as a vitamin K antagonist, meaning it reduces the ability of blood to clot. This effect is beneficial in preventing and treating various conditions where blood clots can be dangerous, such as deep vein thrombosis (DVT), pulmonary embolism (PE), and stroke in individuals with certain heart conditions like atrial fibrillation or prosthetic heart valves. Warfarin is an oral medication that requires careful monitoring by healthcare professionals due to its narrow therapeutic index and significant potential for interactions with other medications and foods. (Mayo Clinic, MedlinePlus)

Deep dive

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Known interactions

  • Category rule: supplement × medication
    Note

    Some supplements change how the body processes medications (absorption, liver enzymes, or additive effects).

    Specific pairs are checked against a licensed drug database and shown with their own severity. Always confirm with your provider or pharmacist.

  • Category rule: vitamin × medication
    Note

    Certain vitamins interact with specific medications (e.g., vitamin K with blood thinners).

    Specific pairs are checked against a licensed source; confirm with your provider.

  • Compound-pair rule
    Caution

    Additive antiplatelet/antithrombotic effect increases bleeding risk.

    Discuss with prescribing clinician; monitor for bruising, prolonged bleeding, and dose adjustments.

  • Compound-pair rule
    Caution

    Additive antiplatelet/antithrombotic effect increases bleeding risk.

    Discuss with prescribing clinician; monitor for bruising, prolonged bleeding, and dose adjustments.

  • Compound-pair rule
    Caution

    Additive antiplatelet/antithrombotic effect increases bleeding risk.

    Discuss with prescribing clinician; monitor for bruising, prolonged bleeding, and dose adjustments.

  • Compound-pair rule
    Caution

    Additive antiplatelet/antithrombotic effect increases bleeding risk.

    Discuss with prescribing clinician; monitor for bruising, prolonged bleeding, and dose adjustments.

  • Compound-pair rule
    Caution

    Additive antiplatelet/antithrombotic effect increases bleeding risk.

    Discuss with prescribing clinician; monitor for bruising, prolonged bleeding, and dose adjustments.

  • Compound-pair rule
    Caution

    Additive antiplatelet/antithrombotic effect increases bleeding risk.

    Discuss with prescribing clinician; monitor for bruising, prolonged bleeding, and dose adjustments.

  • Compound-pair rule
    Caution

    Additive antiplatelet/antithrombotic effect increases bleeding risk.

    Discuss with prescribing clinician; monitor for bruising, prolonged bleeding, and dose adjustments.

  • Compound-pair rule
    Caution

    Additive antiplatelet/antithrombotic effect increases bleeding risk.

    Discuss with prescribing clinician; monitor for bruising, prolonged bleeding, and dose adjustments.

  • Compound-pair rule
    Caution

    Vitamin K reverses vitamin K antagonist activity and shifts INR.

    Keep vitamin K intake consistent; do not start or stop supplementation without INR monitoring.

  • Compound-pair rule
    Caution

    Vitamin K2 can shift INR on warfarin.

    Discuss with prescribing clinician before adding K2.

Frequently asked

Sources referenced

* American Heart Association * Cochrane Review * DrugBank * Examine.com * FDA Label for Warfarin * Mayo Clinic * MedlinePlus * NIH National Heart, Lung, and Blood Institute * NIH Office of Dietary Supplements (ODS)

Stackwise compiles summaries from publicly available scientific and regulatory references. Always verify important decisions with a licensed clinician.

Related compounds

Others in the medication category or studied for the same goals.

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