Calcium channel blocker · Antihypertensive
Nicardipine (Cardene)
Also called Cardene
Indications
- Hypertensive emergency or severe hypertension when oral therapy is not feasible
- Acute ischemic stroke around reperfusion, and intracerebral hemorrhage
- Subarachnoid hemorrhage until the aneurysm is secured
- Aortic dissection, after a beta-blocker
- Perioperative hypertension, including cardiac surgery and craniotomy
- Preeclampsia when first-line drugs fall short
- Intra-arterial treatment of cerebral vasospasm (off-label)
Dosing
Nicardipine drip card and mL/h converterStart: 5 mg/h
Mechanism of action
Nicardipine is a dihydropyridine that blocks L-type (Cav1.2) calcium channels by binding the α1C subunit, with highest affinity for inactivated channels. Arteriolar smooth muscle rests at a less negative potential than heart muscle, so more of its channels are inactivated and the drug acts on vessels far more than on contractility or the SA and AV nodes. Less calcium entry means less calcium–calmodulin activation of myosin light-chain kinase, so arterioles relax and SVR falls.
Pharmacology
- Cardiovascular: arteriolar dilation lowers SVR and BP; veins are spared, so preload is kept
- Cardiovascular: reflex tachycardia and a rise in cardiac output; little direct effect on contractility or AV conduction
- Cardiovascular: dilates coronary arteries, yet angina appeared or worsened in under 1% of coronary patients in label trials
- CNS: dilates cerebral arteries; headache is the most common side effect
Pharmacokinetics
| Onset | Minutes; without a bolus, half the final BP drop takes about 45 min |
|---|---|
| Duration | About half the effect is gone 30 min after stopping |
| Half-life | 2.7 min, 45 min and 14.4 h phases; the last appears after long infusions |
| Distribution | Lipophilic; Vd 8.3 L/kg; levels creep toward steady state over 24–48 h |
| Protein binding | Over 95% |
| Metabolism | Hepatic CYP3A4, 2C8 and 2D6; it also inhibits CYP3A4 |
| Elimination | Metabolites in urine (49%) and feces (43%); none unchanged |
| Organ failure | Higher levels in liver or kidney impairment: titrate slowly |
Chemistry
- 1,4-Dihydropyridine with a meta-nitrophenyl ring at C4 and two different esters, one carrying a basic N-benzyl-N-methylaminoethyl group
- Racemic: C4 is chiral because the two esters differ
- Lipophilic (log P about 3.8), but the basic amine (pKa roughly 7–8) lets the hydrochloride dissolve in acidic water, so it needs no lipid vehicle
- Premixed 0.1 or 0.2 mg/mL in 200 mL of dextrose or saline with sorbitol and citric acid; iso-osmotic, pH 3.7–4.7
- Light oxidizes dihydropyridines to inactive pyridines: keep bags in the carton until use; run no other drug in the line
Adverse effects and cautions
In the one-pagers
- Aortic Dissection and Hypertensive EmergencyAortic dissection: Beta-blocker FIRST (esmolol or labetalol), then a vasodilator (nicardipine, clevidipine or nitroprusside) if BP stays high
- Subarachnoid HemorrhageUntil the aneurysm is secured: BP: frequent checks; nicardipine, clevidipine or labetalol; avoid MAP below 65 and swings. No proven target; many units keep SBP below 160, some below 140 (ESO 2026 consensus: about 160, lowered gradually).
- After Cardiac SurgeryHemodynamics, low output and vasoplegia: Afterload: hypertension strains suture lines and raises bleeding; use nicardipine, clevidipine or nitroprusside, or nitroglycerin when ischemia or radial spasm is the worry. After mitral repair for regurgitation the LV loses its low-pressure outlet into the atrium and tolerates afterload poorly.
- Endocrine EmergenciesPheochromocytoma crisis: Lower pressure with α-blockade or an arterial vasodilator: phentolamine 1–5 mg IV boluses or infusion, nicardipine, clevidipine or nitroprusside. Add esmolol for tachycardia only after α-blockade; labetalol alone is a poor choice because its IV β effect is about 7 times its α effect. Patients are volume-contracted, so expand volume as vessels relax. Catecholamine cardiomyo
- Obstetric EmergenciesPreeclampsia with severe features, eclampsia and HELLP: For sustained control, PB 222 also lists infusions of labetalol 1–2 mg/min or hydralazine 0.5–10 mg/h, and ICUs often use nicardipine. Aim for a safe range, not normal, because placental flow follows maternal pressure: 130–150/80–100 in the 2025 ACOG/NAEMSP guideline, 135/85 in NICE NG133. NSAIDs remain preferred over opioids for postpartum p
- Peripheral Vascular EmergenciesCarotid endarterectomy and stenting in depth: Hyperperfusion syndrome: after a tight stenosis is opened, flow can exceed what the brain's autoregulation can handle. Signs are a severe headache on the operated side, eye or facial pain, seizures, focal deficits and confusion, usually with high blood pressure; intracerebral hemorrhage is the feared result. In the review by Zhou et al., pooled inciden
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Sources
- FDA label: Cardene IV (2026)
- PubChem: nicardipine
For education and exam preparation only. Follow your institution’s protocols. Typical adult values for study. Follow the order, the label and your institution's protocols.