Used primarily as an antiarrhythmic agent to treat and prevent various types of irregular heartbeats, including atrial fibrillation and ventricular arrhythmias. It works by blocking sodium channels in cardiac tissue, which slows down electrical conduction in the heart and helps restore normal rhythm. Often prescribed for patients with symptomatic arrhythmias when other treatments are not effective or tolerated. Also utilized in managing supraventricular tachycardias in certain clinical settings.