Used primarily in the treatment of chronic angina, ranolazine dihydrochloride helps improve exercise tolerance and reduce angina frequency by modulating cardiac ion channels. It works by inhibiting the late sodium current in heart cells, which reduces intracellular calcium overload and decreases myocardial oxygen demand. This mechanism makes it effective even when combined with other anti-anginal drugs like beta-blockers or calcium channel blockers. It is prescribed for patients who do not achieve sufficient symptom control with first-line therapies. Additionally, ranolazine has shown potential in managing certain cardiac arrhythmias due to its stabilizing effect on electrical activity in the heart.