Skip to content

    Phenytoin Sodium Extended



    This information is generalized and not intended as specific medical advice. Consult your healthcare professional before taking or discontinuing any drug or commencing any course of treatment.

    Medical warning:

    Moderate. These medicines may cause some risk when taken together. Contact your healthcare professional (e.g. doctor or pharmacist) for more information.

    How the interaction occurs:

    Your seizure medicine may decrease the effects of your metyrapone.

    What might happen:

    When taking these two medicines together, the results of your metyrapone test may not be accurate.

    What you should do about this interaction:

    Talk to your healthcare professionals (e.g. doctor or pharmacist) before you have your test. It may be necessary to adjust the dose of the metyrapone used in the test.Your healthcare professionals may already be aware of this interaction and may be monitoring you for it. Do not start, stop, or change the dosage of any medicine before checking with them first.


    1.Krieger DT. Effect of diphenylhydantoin on pituitary-adrenal interrelations. J Clin Endocrinol Metab 1962 May;22(5):490-3.

    2.Werk EE Jr, Thrasher K, Choi Y, Sholiton LJ. Failure of metyrapone to inhibit 11-hydroxylation of 11-deoxycortisol during drug therapy. J Clin Endocrinol Metab 1967 Sep;27(9):1358-60.

    3.Meikle AW, Jubiz W, Matsukura S, West CD, Tyler FH. Effect of diphenylhydantoin on the metabolism of metyrapone and release of ACTH in man. J Clin Endocrinol Metab 1969 Dec;29(12):1553-8.

    4.Jubiz W, Levinson RA, Meikle AW, West CD, Tyler FH. Absorption and conjugation of metyrapone during diphenylhydantoin therapy: mechanism of the abnormal response to oral metyrapone. Endocrinology 1970 Feb; 86(2):328-31.

    Selected from data included with permission and copyrighted by First Databank, Inc. This copyrighted material has been downloaded from a licensed data provider and is not for distribution, expect as may be authorized by the applicable terms of use.

    CONDITIONS OF USE: The information in this database is intended to supplement, not substitute for, the expertise and judgment of healthcare professionals. The information is not intended to cover all possible uses, directions, precautions, drug interactions or adverse effects, nor should it be construed to indicate that use of a particular drug is safe, appropriate or effective for you or anyone else. A healthcare professional should be consulted before taking any drug, changing any diet or commencing or discontinuing any course of treatment.

    More about Drugs and Medications

    URAC Seal TRUSTe Privacy Certification TAG Registered Seal HONcode Seal AdChoices