Amiodarone is a type of antiarrhythmic medication that works by preventing irregular heart rhythms. It’s used to treat various types of cardiac arrhythmias or heart rhythm problems, including those caused by cardiac arrest or ischemic attacks such as strokes. When administered through an intravenous infusion (IV), amiodarone works quickly and effectively to treat life-threatening arrhythmias. When taken orally, amiodarone produces longer-acting effects which make it more useful for certain conditions that require long-term treatment.