Structure
Quinidine Sulfate Chemical Structure – C40H50N4O8S
Mode of action
This medication affects sodium channels in Purkinje fibres, which transmits its antiarrhythmic effects.
The main mechanism of action of quinidine is inhibiting the rapid inward sodium current.
The impact of quinidine on fast inward sodium current is termed to as a "usage dependent block." Accordingly, the block grows at faster heart rates while shrinking at slower rates.
The cardiac action potential's phase 0 depolarization is decreased because of blocking the rapid inward sodium current.
Uses
Quinidine is used to treat ventricular arrhythmias,
It is used to treat atrial fibrillation, and flutter.
Also used to return the body's natural sinus rhythm.
Sometimes it is used to treat malaria as an alternate of quinine.