Discovered in 1961 by Tondeur and Binon, two Belgian chemists, amiodarone was widely used, especially in Europe, initially as an antianginal agent, and later as an antiarrhythmic one (following the experiments conducted at the University of Oxford by Dr. Bramah Singh). Thus, the role of amiodarone was reconsidered, becoming, together with Sotalol, a class III antiarrhythmic--a group characterized by the action of extending the potassium channels refractory period. In time, amiodarone has proven its effectiveness in the treatment of both atrial and potentially malignant ventricular arrhythmias, being considered one of the antiarrhythmic agents involved in the prevention of sudden cardiac death due to arrhythmias. In December 1985, amiodarone was approved by the FDA (Food and Drug Administration) for the treatment of atrial fibrillation and the prevention of recurrent ventricular tachycardias. Despite this positive effect, the prescription of amiodarone began to be limited because serious side effects occurred, some of them disastrous, which were associated with the chronic use of the substance.