The present chapter Amiodarone (AMD) was discovered by accidental observation by Gleb von Anrep in 1946 and has significant cardioactive properties to improve angina and thus led to the European pharmaceutical industries to isolate an active compound. The two-dimensional and three-dimensional ball structure of the AMD molecule with formula C25H29I2NO3 molecular mass is 64,531 g/mmol and its molecular structure contains the iodine moiety which was supposed to be the source of the effects as well as the side effects. The chapter also mentions on electrophysiological properties, four classes of antiarrhythmic drugs based on their actions on the action potential curve Class I, Class II Class III and Class IV. The chapter outlines the metabolism, evidences with some key trials with the drug, adverse effects of amiodarone and finally concludes the remarks with It is indicated in various dysrhythmias, however, is associated with mild to severe adverse effects, some of which are reversible after stopping the drug. Monitoring of the administration of the drugs in terms of dose and duration is very essential to avoid the side effects.