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Propafenone/Class IA and III Antiarrhythmics

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:

Severe. These medicines may interact and cause very harmful effects and are usually not taken together. Contact your healthcare professional (e.g. doctor or pharmacist) for more information.

How the interaction occurs:

Both propafenone and Class IA and III antiarrhythmics can affect your heart's rhythm. Quinidine may slow down how quickly your liver processes propafenone.

What might happen:

Taking propafenone with other antiarrhythmics can affect your heart rhythm and may increase your risk of an irregular heartbeat, which may be life-threatening. If the other antiarrhythmic is quinidine, the amount of propafenone in your blood may increase.

What you should do about this interaction:

Let your healthcare professionals (e.g. doctor or pharmacist) know right away that you are taking these medicines together. Your doctor may want to check the rhythm of your heart or the amount of propafenone in your blood. Let your doctor know right away if you notice an irregular heartbeat or have any dizziness or fainting episodes.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.Rythmol (propafenone hydrochloride) US prescribing information. Abbott Laboratories March, 2013.

2.Funck-Brentano C, Kroemer HK, Pavlou H, Woosley RL, Roden DM. Genetically-determined interaction between propafenone and low dose quinidine: role of active metabolites in modulating net drug effect. Br J Clin Pharmacol 1989 Apr;27(4):435-44.

3.Gonzalez FJ, Skoda RC, Kimura S, Umeno M, Zanger UM, Nebert DW, Gelboin HV, Hardwick JP, Meyer UA. Characterization of the common genetic defect in humans deficient in debrisoquine metabolism. Nature 1988 Feb 4; 331(6155):442-6.

4.Klein RC, Huang SK, Marcus FI, Horwitz L, Fenster PE, Rushforth N, Kirsten EB. Enhanced antiarrhythmic efficacy of propafenone when used in combination with procainamide or quinidine. Am Heart J 1987 Sep; 114(3):551-8.

5.Korantzopoulos P, Kolettis TM, Papathanasiou A, Naka KK, Kolios P, Leontaridis I, Draganigos A, Katsouras CS, Goudevenos JA. Propafenone added to ibutilide increases conversion rates of persistent atrial fibrillation. Heart 2006 May;92(5):631-4.

6.Chiladakis JA, Kalogeropoulos A, Patsouras N, Manolis AS. Ibutilide added to propafenone for the conversion of atrial fibrillation and atrial flutter. J Am Coll Cardiol 2004 Aug 18;44(4):859-63.

7.Lau CP, Chow MS, Tse HF, Tang MO, Fan C. Control of paroxysmal atrial fibrillation recurrence using combined administration of propafenone and quinidine. Am J Cardiol 2000 Dec 15;86(12):1327-32.

8.Morgera T, Dreas L, Humar F, Maras P, Chersevani D, Camerini F. The use of associated propafenone in patients with amiodarone-resistant ventricular tachycardia. Int J Cardiol 1991 May;31(2):187-97.

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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