Nicardipine Overview and Clinical Use

Nicardipine Overview

• Nicardipine is a calcium channel blocker (CCB).
• It is a dihydropyridine CCB.
• Primarily used as an antihypertensive agent.
• Used for managing acute hypertension.

Mechanism of Action

• Inhibits calcium ion influx into vascular smooth muscle cells.
• This relaxation causes vasodilation.
• Systemic vasodilation reduces peripheral resistance, lowering blood pressure.

Pharmacokinetics

• Rapidly absorbed orally, but low bioavailability (~30%) due to first-pass metabolism.
• Extensively metabolized in the liver.
• Major metabolites are inactive and cleared by the kidneys.
• Elimination half-life is 5-8 hours.

Clinical Uses

• Treats essential hypertension.
• Used in hypertensive emergencies (e.g., acute stroke, severe preeclampsia).
• Often administered intravenously for rapid onset in emergencies.
• Used for ischemic chest pain refractory to other treatments.
• Used cautiously in patients with severe left ventricular dysfunction or other cardiac conditions.

Administration

• Commonly given intravenously for rapid onset, especially in emergencies.
• Available in oral forms for chronic hypertension management.
• Oral administration has a slower onset of action.

Side Effects

• Common: headache, flushing, dizziness, peripheral edema.
• Less common but serious: hypotension, bradycardia, arrhythmias (especially with IV).
• Reflex tachycardia is a possible adverse effect due to vasodilation.

Contraindications

• Hypersensitivity to nicardipine or other dihydropyridine CCBs.
• Caution with severe hypotension, acute myocardial infarction, or severe hepatic dysfunction.
• Use during pregnancy and lactation only if benefits outweigh risks.

Drug Interactions

• Significant interactions with other vasodilators, antihypertensives, and medications affecting hepatic metabolism.
• Caution when combining with medications decreasing cardiac output.

Dosage Considerations

• Individualized based on patient response and continuous blood pressure monitoring.
• IV nicardipine starting dose and titration carefully adjusted based on initial blood pressure and clinical status.
• Oral dosage adjustments with careful blood pressure monitoring and adverse effect observation.

Special Considerations

• Secondary choice for hypertension management if first-line agents are ineffective or poorly tolerated.
• Patient education on potential side effects, and the need for regular blood pressure monitoring, is crucial.