Quinidine – A Natural Alkaloid with a Timeless Role in Cardiac Care

Quinidine, an alkaloid found naturally in cinchona, has been used extensively in cardiology for more than a century. Since its first isolation as a stereoisomer of quinine from Cinchona bark, it has been extensively utilised in the management and prevention of ventricular and atrial arrhythmias [1,2]. Quinidine, an antiarrhythmic drug that falls under Vaughan-Williams Class Ia, mainly inhibits sodium channels, which lengthens the action potential and refractory period [4,5]. It is still essential in specific situations, such as Brugada syndrome, short QT syndrome, and some hereditary arrhythmias [3,10,15], even though its broad use has decreased because of the risk of proarrhythmia and the availability of safer antiarrhythmic medications [6]. Quinidine's history, pharmacology, clinical use, safety issues, and changing function in contemporary treatment are all well covered in this review.