Is Nicardipine a Calcium Channel Blocker?
Yes, nicardipine is definitively a calcium channel blocker (CCB), specifically a dihydropyridine-type calcium channel blocker. 1
Drug Classification
Nicardipine hydrochloride is classified as a calcium ion influx inhibitor (also termed a slow channel blocker or calcium channel blocker) that inhibits the transmembrane influx of calcium ions into cardiac muscle and smooth muscle. 1, 2
Nicardipine belongs to the dihydropyridine subclass of CCBs, which have high selectivity for L-type calcium channels in the vasculature and produce decreased coronary and systemic vascular resistance. 3, 1
The drug is more selective for vascular smooth muscle than cardiac muscle, producing relaxation of coronary vascular smooth muscle at drug levels that cause little or no negative inotropic effect. 2
Clinical Applications Confirming CCB Status
Multiple authoritative guidelines explicitly identify nicardipine as a CCB in various clinical contexts:
The 2017 ACC/AHA hypertension guidelines list nicardipine as a CCB in their table of intravenous antihypertensive drugs for hypertensive emergencies, noting it is favored in North America for blood pressure management. 3
Nicardipine is recommended as a preferred CCB for multiple hypertensive emergency scenarios including acute coronary syndromes, acute renal failure, eclampsia/preeclampsia, and perioperative hypertension. 3
The 2009 AHA/ASA guidelines describe nicardipine as "an intravenous preparation of a similar L-type calcium channel blocker" (comparing it to nimodipine), demonstrating a 30% reduction in cerebral vasospasm after subarachnoid hemorrhage. 3
Distinguishing Features Among CCBs
Nicardipine differs from non-dihydropyridine CCBs (verapamil and diltiazem) in important ways:
Dihydropyridines like nicardipine have more pronounced peripheral arterial vasodilatory effects and higher rates of peripheral edema compared to non-dihydropyridines. 4
Unlike verapamil and diltiazem, nicardipine has minimal effects on cardiac pacemaker and atrioventricular conduction cells, resulting in less negative inotropic and chronotropic effects. 3
Nicardipine is available in intravenous formulation, making it the first intravenously administered dihydropyridine CCB, which distinguishes it from oral-only agents like nifedipine. 1, 5