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metoprolol tartrate



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 medicines are taken together, your body may process your beta-blocker medicine more slowly.

What might happen:

Your blood levels of the beta-blocker medicine may increase and cause abnormally low blood pressure.

What you should do about this interaction:

Contact your doctor if you experience a slowed heartbeat, or dizziness and weakness, especially upon standing.If your doctor prescribes these medicines together, you may be asked to take your medicine with food or to use a sustained-release form of your beta-blocker.Your healthcare professionals (e.g. doctor or pharmacist) 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.Zacest R, Gilmore E, Koch-Weser J. Treatment of essential hypertension with combined vasodilation and beta- adrenergic blockade. N Engl J Med 1972 Mar 23;286(12):617-22.

2.Guevara J, Velasco M, Hernandez-Pieretti O. Treatment of severe essential hypretension with combined hydralazine and propranolol. Curr Ther Res 1977 Mar;21(3):277-281.

3.McLean AJ, Skews H, Bobik A, Dudley FJ. Interaction between oral propranolol and hydralazine. Clin Pharmacol Ther 1980 Jun;27(6):726-32.

4.Jackman GP, McLean AJ, Jennings GL, Bobik A. No stereoselective first-pass hepatic extraction of propranolol. Clin Pharmacol Ther 1981 Sep; 30(3):291-6.

5.Schneck DW, Vary JE. Mechanism by which hydralazine increases propranolol bioavailability. Clin Pharmacol Ther 1984 Apr;35(4):447-53.

6.Byrne AJ, McNeil JJ, Harrison PM, Louis W, Tonkin AM, McLean AJ. Stable oral availability of sustained release propranolol when co- administered with hydralazine or food: evidence implicating substrate delivery rate as a determinant of presystemic drug interactions. Br J Clin Pharmacol 1984; 17 Suppl 1:45S-50S.

7.Lindeberg S, Holm B, Lundborg P, Regardh CG, Sandstrom B. The effect of hydralazine on steady-state plasma concentrations of metoprolol in pregnant hypertensive women. Eur J Clin Pharmacol 1988;35(2):131-5.

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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