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Phenytoin-misonidazole: possible metabolic interaction

D Gangji, J G Schwade, J M Strong

    Cancer Treatment Reports
    |January 1, 1980
    PubMed

    Insights

    Misonidazole

    Area of Science:

    • Pharmacology
    • Clinical Pharmacy

    Background:

    • Misonidazole is an investigational drug.
    • Phenytoin is an anti-epileptic drug with a narrow therapeutic index.

    Purpose of the Study:

    • To investigate the pharmacokinetic interaction between misonidazole and phenytoin.

    Main Methods:

    • Intravenous administration of misonidazole.
    • Observation of misonidazole plasma half-life and metabolism in a patient on chronic phenytoin therapy.

    Main Results:

    • Misonidazole exhibited a significantly decreased plasma half-life (3.8 hours) in the patient receiving phenytoin, compared to controls (9.1 hours +/- 0.8).
    • Increased metabolism of misonidazole was observed in the patient on phenytoin therapy.

    Conclusions:

    • Continuous phenytoin therapy may alter the pharmacokinetics of misonidazole.
    • Phenytoin may increase the metabolism of misonidazole, leading to a reduced half-life.

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