Diltiazem (DB00343): A Comprehensive Pharmacological and Clinical Monograph

Section I: Executive Summary

Diltiazem is a non-dihydropyridine calcium channel blocker of the benzothiazepine class, distinguished by its balanced effects on both cardiac tissue and vascular smooth muscle. Its primary mechanism of action involves the inhibition of L-type calcium channels, which results in a constellation of therapeutic effects, including negative chronotropy (reduced heart rate), dromotropy (slowed atrioventricular conduction), and mild negative inotropy (reduced cardiac contractility), coupled with potent coronary and peripheral vasodilation.

Clinically, diltiazem is well-established for the management of hypertension, chronic stable angina, and variant (Prinzmetal's) angina. In its intravenous formulation, it is a cornerstone for the acute management of supraventricular arrhythmias, particularly for rate control in atrial fibrillation or flutter and for the conversion of paroxysmal supraventricular tachycardia. Its therapeutic scope has expanded to include numerous off-label applications, such as the topical treatment of anal fissures, and it is the subject of significant investigational research for disease modification in preclinical hypertrophic cardiomyopathy, treatment of coronary microvascular dysfunction, and even as a potential anticancer agent through a newly discovered mechanism involving urokinase receptor (uPAR) inhibition.