Perhexiline maleate is primarily used in the treatment of angina pectoris, a condition characterized by chest pain due to reduced blood flow to the heart. It works by improving the efficiency of oxygen utilization in the heart muscle, thereby reducing the frequency and severity of angina attacks. This makes it particularly useful for patients who do not respond well to other anti-anginal medications. Additionally, it has been explored for its potential benefits in managing certain types of heart failure and arrhythmias, although its use in these areas is less common. Due to its narrow therapeutic window, careful monitoring of blood levels is essential to avoid toxicity. It is also sometimes used off-label for conditions like hypertrophic cardiomyopathy, where it can help alleviate symptoms by improving myocardial metabolism.