Diltiazem is a member of the group of drugs known as Benzothiapines , which are a class of calcium channel blockers, used in the treatment of hypertension, angina pectoris, and some types of arrhythmia. It is a class 3 anti anginal drug, and a Class IV antidysrhythmic. It incites very minimal reflex sympathetic changes.

Diltiazem is a potent vasodilator, increasing blood flow and variably decreasing the heart rate via strong depression of A-V node conduction.

Diltiazem is metabolized by and acts as an inhibitor of the CYP3A4 enzyme.

Diltiazem is contraindicated in the presence of Sick sinus syndrome, Atrioventricular node conduction disturbances, Bradycardia, impaired Left ventricle function, Peripheral artery occlusive disease, Chronic obstructive pulmonary disease, and Prinzmetal's angina.