Ethacizine (ethacyzine) is a class Ic antiarrhythmic agent, related to moracizine. It is used in Russia and some other Commonwealth of Independent States countries for the treatment of severe and/or refractory ventricular and supraventricular arrhythmias, especially those accompanied by organic heart disease. It is also indicated as a treatment of refractory tachycardia associated with Wolff–Parkinson–White syndrome.

Ethacizine (ethacyzine) is a class Ic antiarrhythmic agent, related to moracizine. It is used in Russia and some other Commonwealth of Independent States countries for the treatment of severe and/or refractory ventricular and supraventricular arrhythmias, especially those accompanied by organic heart disease. It is also indicated as a treatment of refractory tachycardia associated with Wolff–Parkinson–White syndrome.