Diltiazem is a nondihydropyridine calcium channel blocker medication used to treat high blood pressure, angina, and certain heart arrhythmias.
It is prescribed off-label by doctors in the US for prophylaxis of cluster headaches.
Diltiazem is indicated for:
- Stable angina (exercise-induced) – diltiazem increases coronary blood flow and decreases myocardial oxygen consumption, secondary to decreased peripheral resistance, heart rate, and contractility
- Variant angina – it is effective owing to its direct effects on coronary dilation
- Unstable angina (preinfarction, crescendo) – diltiazem may be particularly effective if the underlying mechanism is vasospasm
- Myocardial bridge
For supraventricular tachycardias (PSVT), diltiazem appears to be as effective as verapamil in treating re-entrant supraventricular tachycardia.
It is also used as topical application for anal fissures because it promotes healing due to its vasodilatory property.
Recent research has shown diltiazem may reduce cocaine cravings in drug-addicted rats.
This is believed to be due to the effects of calcium blockers on dopaminergic and glutamatergic signaling in the brain.
Diltiazem also enhances the analgesic effect of morphine in animal tests, without increasing respiratory depression, and reduces the development of tolerance.
