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    Cheratussin DAC


    Narcotic Analgesics/Cimetidine

    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:

    The cause of the interaction is not known. When these medicines are taken together your body may not process your pain medicine properly.

    What might happen:

    You may experience excessive drowsiness, sluggishness, and disorientation. You may experience shortness of breath or have difficulty breathing.

    What you should do about this interaction:

    Contact your healthcare professional (e.g. doctor or pharmacist) if you experience excessive drowsiness or have trouble breathing. Your doctor may want to adjust the dose of your pain medicine.Contact your healthcare professional (e.g. doctor or pharmacist) as soon as possible about taking these two medicines together.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.Philbin DM, Moss J, Akins CW, Rosow CE, Kono K, Schneider RC, VerLee TR, Savarese JJ. The use of H1 and H2 histamine antagonists with morphine anesthesia: a double-blind study. Anesthesiology 1981 Sep;55(3):292-6.

    2.Fine A, Churchill DN. Potentially lethal interaction of cimetidine and morphine. Can Med Assoc J 1981 Jun 1;124(11):1434-6.

    3.Sorkin EM, Ogawa GS. Cimetidine potentiation of narcotic action. Drug Intell Clin Pharm 1983 Jan;17(1):60-1.

    4.Guay DR, Meatherall RC, Chalmers JL, Grahame GR. Cimetidine alters pethidine disposition in man. Br J Clin Pharmacol 1984 Dec;18(6):907-14.

    5.Lam AM, Clement JL. Effect of cimetidine premedication on morphine-induced ventilatory depression. Can Anaesth Soc J 1984 Jan;31(1):36-43.

    6.Guay DR, Meatherall RC, Chalmers JL, Grahame GR, Hudson RJ. Ranitidine does not alter pethidine disposition in man. Br J Clin Pharmacol 1985 Jul; 20(1):55-9.

    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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