The exact mechanism is somewhat controversial, however it likely inhibits sodium channels eventually reducing intracardiac calcium causing reduced oxygen consumption. Initially, ranolazine was thought to shift the main energy substrate of myocytes from lipid metabolism to glucose metabolism, however this has not been definitively proven at normal doses.

The drug ranolazine is a novel agent to treat angina. Ranolazine does not change any hemodynamic parameters (blood pressure, heart rate, vascular tone). Ranolazine is considered for patients with angina that fail nitrates, beta-blockers and calcium channel blockers. Side effects are relatively uncommon, however ranolazine can prolong the QT interval increasing the risk of polymorphic ventricular tachycardia (Torsades de Pointes).