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A significant interaction between metronidazole and warfarin

F J Kazmier

    Mayo Clinic Proceedings
    |December 1, 1976
    PubMed

    Insights

    Metronidazole (Flagyl) can significantly increase warfarin

    Area of Science:

    • Pharmacology
    • Clinical Toxicology

    Background:

    • Metronidazole, an antibiotic, exhibits a disulfiram-like effect.
    • Warfarin, an anticoagulant, is known to interact with disulfiram.

    Observation:

    • A patient taking both metronidazole and warfarin experienced a clinically significant interaction.

    Findings:

    • This case report confirms a significant drug interaction between metronidazole and warfarin in humans.
    • The interaction likely potentiates warfarin's anticoagulant effect.

    Implications:

    • Clinicians should monitor patients closely when prescribing metronidazole to those on warfarin.
    • Dosage adjustments of warfarin may be necessary during metronidazole therapy.

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