Pharmacology · Calcium channel blockers
Nicardipine !
A dihydropyridine given by continuous IV infusion to lower blood pressure in a controlled way when oral treatment is not possible.
Updated 2026-11-01
The figure shows amlodipine, another dihydropyridine, in the same binding site of the human CaV1.2 channel; no human structure with nicardipine bound is available.
Mechanism of action
Nicardipine blocks L-type calcium channels in arteriolar and coronary smooth muscle, with little effect on contractility or the AV node. Arterioles relax, systemic resistance falls and blood pressure drops in proportion to the infusion; heart rate may rise by reflex.
- Nicardipine blocks L-type calcium channels of arterioles
- Arterioles relax and systemic resistance falls
- Blood pressure falls as the infusion is adjusted
Pharmacokinetics
- Distribution
- Fast early distribution, so the effect follows changes in the infusion
- Metabolism
- Liver; levels rise in severe liver disease
- Half-life
- Effect fades over tens of minutes after stopping; a slow terminal phase appears after long infusions
Indications
- Short-term lowering of blood pressure when oral treatment is not possible, including hypertensive emergencies Arterial hypertension →
Adverse effects
Common
- Headache
- Hypotension
- Reflex tachycardia
- Nausea and vomiting
- Infusion-site phlebitis
Contraindications
- Advanced aortic stenosis
Key interactions
- Beta blockers being withdrawn
- Nicardipine gives no protection against beta-blocker withdrawal; they are tapered
- Cyclosporine or tacrolimus
- Higher immunosuppressant levels; trough levels are followed
- Other antihypertensives or anaesthetics
- Added hypotension
What is monitored
- Blood pressure, very often during titration (arterial line in emergencies)
- Heart rate
- Infusion site
Administration and safety
- Continuous IV infusion by pump, through a central line or a large peripheral vein; never small veins of the hand or wrist
- With a peripheral vein, the infusion site is changed every 12 hours
- Premixed bags: nothing is added to the bag, and it is protected from light until use
Nursing care
- Measure blood pressure and heart rate often and adjust per protocol; stop the infusion if hypotension or tachycardia appears
- Inspect the IV site for pain, redness or swelling
- Avoid lowering pressure faster than ordered, especially after a stroke
- Plan the change to oral antihypertensives before stopping the infusion
Pregnancy and breastfeeding
Human data are limited; it is used in pregnancy only when the benefit justifies the risk.
Test yourself
Think of the answer, then tap the question to see it.
What is the only contraindication of IV nicardipine on its label?
Advanced aortic stenosis, because lowering afterload can drop coronary and cerebral perfusion.
How often is a peripheral infusion site changed with nicardipine?
Every 12 hours, to reduce phlebitis and vein injury.
Does nicardipine protect against beta-blocker withdrawal?
No. It is not a beta blocker, so beta blockers are still tapered gradually.
Related drugs
Related conditions
← Back to the class: Calcium channel blockers
Educational content on how drugs work; not a prescribing guide and no substitute for a health professional's advice. No doses are given.
Sources: DailyMed - NICARDIPINE HYDROCHLORIDE injection (DailyMed (U.S. National Library of Medicine), 2026); ATCDDD - ATC/DDD Index (WHO Collaborating Centre for Drug Statistics Methodology, 2026); Goodman & Gilman's The Pharmacological Basis of Therapeutics, 14th ed., ch. 32 (McGraw Hill, 2023).
Spotted a mistake?We are always improving for the community. Tell us what is wrong and our team will review it.Report a mistake
Representative model, for educational purposes only.