Diltiazem HCl

CAS 33286-22-5

About the API

Systematic name (2S,3S)-5-[2-(dimethylamino)ethyl]-2-(4-methoxyphenyl)-4-oxo-2,3,4,5-tetrahydro-1,5-benzothiazepin-3-yl acetate hydrochloride
Trade name(s) Angiotrofin, Cardizem, Dilacor-XR
Technology Synthetic Organic Chemistry
Molecular Formula C22H27ClN2O4S
Molecular Weight 450.979 g/mol
Therapeutic category Cardiovascular
Available formulations Injectables Nasal Systemic Oral Solid Oral Solid Long-Acting
Regulations Canada DMF Flag Canada DMF CEP Flag CEP EU DMF Flag EU DMF Japan DMF Flag Japan DMF US DMF Flag US DMF

General Information

Diltiazem hydrochloride belongs to the class of benzothiazepine drugs and is indicated for the treatment of hypertension, chest pain (angina), certain types of arrhythmia, and migraine headaches (regardless of pharmacological mechanisms).


Diltiazem is also a potent vasodilator of coronary and peripheral vessels, which makes it an effective treatment for milder forms of hypertension. The drug achieves its dilatory properties by acting as a calcium channel blocker. Accordingly, low blood pressure patients (systolic blood pressures below 90 mmHg) should not be treated with diltiazem.


With first disclosure in 1971 (U.S. Pat. No. 3,562,257), and FDA approval in 1982, diltiazem hydrochloride has been available in numerous generic formulations since the mid 1990’s. Presently, diltiazem is manufactured through an efficient multi-step large-scale organic synthesis protocol starting from simple, commercially available (petrochemical) precursors.