Used primarily as an antiarrhythmic medication to treat and prevent serious ventricular arrhythmhythmias, including ventricular fibrillation and ventricular tachycardia. It is also employed in managing atrial fibrillation and atrial flutter, especially in patients with underlying structural heart disease. Due to its broad-spectrum efficacy, it is often reserved for life-threatening arrhythmias or when other antiarrhythmic drugs have failed. Administered orally or intravenously in hospital settings, it helps maintain normal heart rhythm in patients with recurrent or refractory arrhythmias. Its long half-life allows for once or twice-daily dosing in maintenance therapy.