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    fosphenytoin injection


    Theophyllines/Hydantoins (mono deleted 03/26/2014)

    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:

    When these two medicines are taken together, the effects of one or both medicines may decrease.

    What might happen:

    A decrease in the beneficial effects of one or both medicines may occur.

    What you should do about this interaction:

    If you experience difficulty breathing or your seizure control changes, contact your doctor. It may be necessary to adjust the dose of your medicines.Your healthcare professionals (e.g. doctor or pharmacist) may already be aware of this drug 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.Taylor JW, Hendeles LWeinberger M, Lyon LW, Wyatt R, Riegelman S. The interaction of phenytoin and theophylline. Drug Intell Clin Pharm 1980; 14(9):638.

    2.Marquis JF, Carruthers SG, Spence JD, Brownstone YS, Toogood JH. Phenytoin-theophylline interaction. N Engl J Med 1982 Nov 4; 307(19):1189-90.

    3.Anonymous. Phenytoin-theophylline-quinidine interactions. N Engl J Med 1983 Mar 24;308(12):724-5.

    4.Miller M, Cosgriff J, Kwong T, Morken DA. Influence of phenytoin on theophylline clearance. Clin Pharmacol Ther 1984 May;35(5):666-9.

    5.Sklar SJ, Wagner JC. Enhanced theophylline clearance secondary to phenytoin therapy. Drug Intell Clin Pharm 1985 Jan;19(1):34-6.

    6.Crowley JJ, Cusack BJ, Jue SG, Koup JR, Park BK, Vestal RE. Aging and drug interactions. II. Effect of phenytoin and smoking on the oxidation of theophylline and cortisol in healthy men. J Pharmacol Exp Ther 1988 May; 245(2):513-23.

    7.Adebayo GI. Interaction between phenytoin and theophylline in healthy volunteers. Clin Exp Pharmacol Physiol 1988 Nov;15(11):883-7.

    8.Landsberg K, Shalansky S. Interaction between phenytoin and theophylline. Can J Hosp Pharm 1988 Feb;41(1):31-2.

    9.Nicholson JP, Basile SA, Cury JD. Massive theophylline dosing in a heavy smoker receiving both phenytoin and phenobarbital. Ann Pharmacother 1992 Mar;26(3):334-6.

    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.

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