Nicardipine
Pronunciation: (nye-KAR-di-peen).
- Generic name
- nicardipine
- Brand names
- Nicardipine Hydrochloride Capsules (generic, US), Nicardipine Hydrochloride Injection (generic, US), Cardene / Cardene SR / Cardene IV (US, historical brand, discontinued)
- Drug class
- Calcium Channel Blocker (Dihydropyridine)
- Form
- Oral capsule (20 mg, 30 mg) for chronic stable angina and hypertension; IV injection (2.5 mg/mL) for short-term treatment of hypertension when oral therapy is not feasible.
- Route
- Oral (capsule) and intravenous (injection) — two distinct products with different indications, dosing, and pharmacokinetics.
- Legal status
- Prescription only in the United States for both oral and IV forms. Non-US legal supply classification is largely
Supply Rules Vary
Trade names by country: United States
Australia: · Full directory
What nicardipine is and how it works
Nicardipine is a dihydropyridine calcium channel blocker. The oral capsule is FDA-approved for chronic stable (effort-associated) angina and for hypertension. The IV injection is FDA-approved for short-term treatment of hypertension when oral therapy isn't feasible or desirable, such as during a hypertensive emergency, with a plan to switch to oral therapy once the patient's condition allows. (1) (2)
Oral and IV nicardipine are different products with different dosing and monitoring needs. IV nicardipine is given only in a monitored clinical setting with continuous blood pressure and heart rate monitoring. Dose adjustments for liver or kidney impairment, and review of interacting medicines, need a clinician's direction.
Mechanism of action: how nicardipine works
Nicardipine is a dihydropyridine calcium channel blocker, more selective for vascular smooth muscle than cardiac muscle. Oral: ~35% bioavailability (saturable first-pass hepatic metabolism), >95% protein-bound, hepatically metabolized via CYP2C8/2D6/3A4, terminal half-life averaging 8.6 hours, steady state in 2-3 days with TID dosing. IV: triphasic decline (alpha ~3 min, beta ~45 min, gamma/terminal ~14 hours), clearance 0.4 L/hr/kg, volume of distribution 8.3 L/kg, linear PK over 0.5-40 mg/hr, steady state approached at 24-48 hours. (1) (2)
What nicardipine is used for
Chronic stable angina (oral)
Oral nicardipine capsules are FDA-approved for the management of chronic stable (effort-associated) angina, used alone or together with beta-blockers. (1)
Hypertension (oral)
Oral nicardipine capsules are FDA-approved to treat hypertension, alone or combined with other antihypertensive medicines. (1)
Short-term hypertension treatment when oral therapy isn't feasible (IV)
IV nicardipine is FDA-approved for short-term treatment of hypertension when oral therapy is not feasible or desirable. It is given only in a monitored setting, with a plan to transition back to oral antihypertensive therapy as soon as the patient's condition allows. (2)
Before taking nicardipine
Do not take / not appropriate for
- Do not use nicardipine (oral or IV) if you have a known hypersensitivity to nicardipine. (hypersensitivity) (1) (2)
- Do not use nicardipine if you have advanced aortic stenosis — reducing afterload can worsen the balance of oxygen supply and demand in the heart in this condition. (advanced aortic stenosis) (1) (2)
Tell your clinician about
- Every prescription medicine, nonprescription medicine, vitamin, and supplement you currently use — especially cimetidine, cyclosporine, tacrolimus, digoxin, or beta-blockers.
- Any history of congestive heart failure, angina, or reduced heart pumping function.
- Any liver or kidney disease — dosing needs adjustment.
- If you are pregnant, planning pregnancy, or breastfeeding.
- If you have pheochromocytoma (relevant to IV use monitoring).
How to take nicardipine
- Oral capsules: swallow whole. The FDA label describes an initial dose of 20 mg three times daily for both angina and hypertension, with an effective range of 20-40 mg three times daily; at least 3 days should pass before a dose increase to let steady state be reached.
- For hypertension, blood pressure is typically checked at peak effect (1-2 hours after a dose) and at trough (about 8 hours after a dose) to judge response.
- IV nicardipine is administered only by healthcare professionals via a central line or a large peripheral vein, starting at 5 mg/hour and increased in 2.5 mg/hour steps (every 15 minutes for a gradual reduction goal, every 5 minutes for a more rapid one), up to a maximum of 15 mg/hour, with continuous blood pressure and heart rate monitoring.
- When switching from oral to IV or vice versa, the FDA label gives specific equivalence points (e.g. 20 mg orally every 8 hours is approximately equivalent to 0.5 mg/hour IV; 30 mg every 8 hours to 1.2 mg/hour IV; 40 mg every 8 hours to 2.2 mg/hour IV) — this substitution must be managed by the treating clinician, not self-directed.
- Do not stop nicardipine suddenly without consulting your doctor; abruptly stopping a beta-blocker taken alongside nicardipine also needs a gradual, clinician-directed taper over about 8-10 days, since nicardipine does not protect against beta-blocker withdrawal effects.
Procedures and treatment changes
Tell the treating team before surgery, procedures, or any medicine change. Do not alter treatment without the responsible clinician. (1) (2) (3) (4) (5) (6) (7) (8) (9) (10)
Missed dose
For the oral capsule, contact your prescriber or pharmacist for guidance if you miss a dose. Do not take a double dose to make up for a missed one without their direction. Missed-dose guidance does not apply to the IV form, which is administered and monitored by healthcare professionals.
Overdose
Overdose can cause marked low blood pressure, a very slow heart rate (bradycardia), drowsiness, confusion, and slurred speech; a reported oral overdose case involved a heart rate as low as 20 beats per minute. Seek emergency care immediately for a suspected overdose. Treatment is supportive — positioning, IV fluids, frequent blood pressure checks, and vasopressors for severe hypotension; IV calcium gluconate may help reverse the calcium-channel-blocking effect. There is no specific antidote. (1) (2)
Side effects
The most common side effects relate to nicardipine's vasodilating effect. Rates below come from the FDA label's own clinical trial data and differ somewhat between the angina and hypertension trial populations and between oral and IV use.
Ankle/foot swelling (pedal edema)
What to notice: Swelling of the ankles or feet. In oral trials this occurred in about 7.1% of angina patients and 8.0% of hypertension patients (vs. under 1% on placebo), and it is dose-related.
What to do: Mention it to your clinician, especially if it's significant or bothersome — it usually reflects the drug's normal vasodilating effect rather than heart failure, but should still be reviewed. (1)
Headache, flushing, dizziness, palpitations
What to notice: These were all more common on nicardipine than placebo in both angina and hypertension oral trials (e.g. headache 6.4-8.2%, flushing 5.6-9.7%). IV nicardipine's most common effects were headache (13%), low blood pressure (5%), fast heart rate (4%), and nausea/vomiting (4%).
What to do: Mention persistent or bothersome symptoms to your clinician. For IV use, the infusion team monitors continuously and will adjust the infusion rate or discontinue it, as clinically indicated. (1) (2)
Increased angina
What to notice: About 5.6-7% of oral angina-trial patients had increased frequency, duration, or severity of angina (vs. about 4% on placebo), particularly when starting or increasing the dose.
What to do: Contact your clinician promptly for new or worsening chest pain. (1)
Signs of significant hypotension or heart rhythm change
What to notice: Severe dizziness, fainting, a very fast or very slow or irregular heartbeat.
What to do: Seek prompt medical assessment; for IV nicardipine this is managed immediately by the monitoring clinical team. (1) (2)
Serious warnings
Worsening angina or myocardial infarction on initiation or dose increase — serious
Symptoms: New or worsening chest pain, particularly around starting nicardipine or increasing the dose.
Action: Contact your prescriber promptly for new or worsening chest pain; seek emergency care for severe or persistent chest pain. (1)
Symptomatic hypotension — serious
Symptoms: Marked drop in blood pressure, especially during initiation or IV titration.
Action: For oral use, contact your clinician for severe dizziness or fainting. For IV use, the infusion is discontinued or reduced by the monitoring team if hypotension occurs. (1) (2)
Abrupt beta-blocker withdrawal — serious
Symptoms: Nicardipine does not protect against the effects of suddenly stopping a beta-blocker taken alongside it.
Action: Any beta-blocker taken together with nicardipine should be tapered gradually (about 8-10 days) under clinician direction, not stopped abruptly. (1) (2)
Overdose — emergency
Symptoms: Marked hypotension, bradycardia (as low as 20 bpm reported), drowsiness, confusion, slurred speech.
Action: Seek emergency care immediately. Supportive treatment and IV calcium gluconate may be used; there is no specific antidote. (1) (2)
Interactions
| Medicine or test | Effect | Action |
|---|---|---|
| Cimetidine | Increases nicardipine blood levels. | Your clinician will monitor more closely if these are combined. (1) (2) |
| Cyclosporine | Nicardipine inhibits CYP3A4 and can raise cyclosporine blood levels. | Cyclosporine levels are monitored and the dose adjusted by the transplant/prescribing team if these are combined. (1) (2) |
| Tacrolimus | Similar CYP3A4-mediated interaction — nicardipine can raise tacrolimus levels. | Tacrolimus levels are monitored and the dose adjusted if these are combined. (1) (2) |
| Digoxin | The oral label describes a usually small and variable effect on digoxin levels. | Your clinician may check digoxin levels, especially when starting or stopping nicardipine. (1) |
| Beta-blockers | Generally well tolerated together, with additive blood-pressure-lowering effect; caution is needed in patients with congestive heart failure because of nicardipine's negative inotropic effect in some patients. | Combination is common in practice but requires monitoring, particularly in heart failure. (1) (2) |
| Fentanyl anesthesia (with beta-blockers) | Severe hypotension has been reported with this combination. | Anesthesia teams may need to give additional IV fluids; this is a clinical-setting consideration for IV nicardipine. (1) |
| Grapefruit and grapefruit juice | As a CYP3A4 substrate, nicardipine is expected to interact with grapefruit similarly to other dihydropyridines, though this specific interaction magnitude was not separately quantified in the sources verified for nicardipine itself. | Discuss grapefruit consumption with your clinician or pharmacist. (10) |
Pregnancy, breastfeeding, kidney/liver function, age
Hepatic impairment
In people with severe liver disease, nicardipine levels rise substantially (peak level about 1.8x higher and total exposure about 4x higher than usual, with the drug staying in the body far longer — an average half-life of about 19 hours instead of 8.6 hours). The FDA label recommends starting at a lower dose (20 mg twice daily) with individual titration in this group. (1)
Renal impairment
In people with mild kidney impairment, nicardipine peak level and total exposure were about twice as high as in people with normal kidney function. The FDA label advises careful, gradual dose titration starting from the standard 20 mg three-times-daily dose in this group. (1)
Older adults
Pharmacokinetics are similar to younger adults, but starting at the low end of the dosing range is recommended. (1)
Pregnancy
The FDA label classifies nicardipine under the older Pregnancy Category C system (a framework FDA has since moved away from for newer labeling generally): animal studies showed fetal harm at some doses tested, and there are no adequate, well-controlled human studies. Nicardipine should be used in pregnancy only if the potential benefit justifies the potential risk to the fetus — this decision belongs with your obstetric care team. (1) (2)
Breastfeeding — two authoritative sources genuinely disagree
This is a case where two authoritative sources reach different conclusions from related data, and both should be considered rather than just one. The FDA prescribing label states that women who wish to breastfeed should not take nicardipine, based on measurable levels of the drug in breast milk. The NIH's LactMed database, reviewing similar milk-level data (estimated infant exposure under 0.3 mcg/day, well under 1% of a therapeutic infant dose), concludes that the amount an infant would ingest is small and would not be expected to cause adverse effects, and states no special precautions are required; it lists nifedipine as an alternative calcium channel blocker some clinicians may prefer during lactation regardless. Discuss this directly with your prescriber and your baby's pediatric provider — do not decide this alone from either source in isolation. (1) (2) (3)
Monitoring
Before starting
- Confirm whether the oral or IV product is intended — they have different dosing and monitoring needs.
- Review liver and kidney function, since both affect dosing.
- Review all current medicines, especially cimetidine, cyclosporine, tacrolimus, digoxin, and beta-blockers.
- Discuss pregnancy, pregnancy plans, and breastfeeding, including the FDA-label/LactMed divergence above.
During treatment
- Blood pressure and heart rate monitoring at initiation and with any dose change; for oral hypertension dosing this includes checking response at both peak (1-2 hours post-dose) and trough (about 8 hours post-dose).
- Continuous blood pressure and heart rate (and typically ECG) monitoring throughout an IV infusion, in a setting equipped for this.
- Watch for increased or new chest pain, particularly at initiation or a dose increase.
- Watch for signs of fluid retention/edema and distinguish this from true heart failure with your clinician.
- If a beta-blocker is being stopped, taper gradually (about 8-10 days) rather than stopping abruptly.
Storage
Store oral capsules at 20-25°C (68-77°F) in a tightly closed, light-resistant, child-resistant container. IV nicardipine is prepared and stored by healthcare professionals according to institutional procedures.
Study the drug class: Dihydropyridine calcium channel blockers
Professional information
Clinician-facing context only. Use the current product-specific US prescribing information and complete medication review. Non-US product, brand, and supply information is limited to what is explicitly documented in country-brand-verification.json and country-supply-classification.json — do not extrapolate beyond it.
United States — oral
Indication: Chronic stable angina; hypertension
Dose summary: Initial 20 mg PO TID; effective range 20-40 mg TID; allow ≥3 days between dose increases (steady state reached in 2-3 days). Hepatic impairment: start 20 mg BID with individual titration (severe disease: Cmax ~1.8x, AUC ~4x higher, t½ ~19h vs 8.6h). Renal impairment: careful titration from standard starting dose (mild impairment: Cmax/AUC ~2x higher).
Renal context: Mild renal impairment approximately doubles Cmax/AUC vs. healthy controls; no separate numeric dose ceiling given in the label beyond careful titration. (1)
United States — IV
Indication: Short-term hypertension treatment when oral therapy not feasible/desirable
Dose summary: Start 5 mg/hr, increase in 2.5 mg/hr increments (every 15 min for gradual reduction, every 5 min for rapid reduction), max 15 mg/hr. Oral-to-IV substitution: 20 mg q8h PO ≈ 0.5 mg/hr IV; 30 mg q8h PO ≈ 1.2 mg/hr IV; 40 mg q8h PO ≈ 2.2 mg/hr IV. Dilute 25 mg vial in 240 mL compatible fluid for 0.1 mg/mL concentration. Change peripheral infusion site every 12 hours.
Renal context: Same caution as oral form; label advises close monitoring in hepatic/renal impairment for IV use, no separate IV-specific numeric adjustment given. (2)
United Kingdom
Indication: Not established from the sources reviewed: an active MHRA substance licence exists but the specific current product/indication could not be confirmed by this pass's tooling.
Dose summary: Not stated; do not infer from US dosing without direct UK label confirmation.
Renal context: Not available. (4)
Australia
Indication: Not established from the sources reviewed: conflicting sources (see country-brand-verification.json).
Dose summary: Not stated.
Renal context: Not available. (5)
Canada
Indication: No currently marketed product identified — see country-supply-classification.json for the three supporting findings.
Dose summary: Not applicable — do not state a Canadian dosing regimen.
New Zealand
Indication: IV nicardipine only, Pharmac-funded since 2015, restricted to anaesthetists/intensivists/paediatric cardiologists. Oral NZ status unresolved.
Dose summary: Not stated for NZ specifically; refer to the funded product's own data sheet, not this draft, for exact NZ dosing.
Renal context: Not available. (9)
Hepatic guidance
Severe hepatic impairment: Cmax ~1.8x and AUC ~4x higher than normal, terminal half-life extended to ~19 hours; start 20 mg BID (oral) with individual titration.
Overdose note
Overdose produces marked hypotension, bradycardia, drowsiness, confusion, slurred speech; supportive care, vasopressors, and IV calcium gluconate as needed; no specific antidote. (1) (2)
Frequently asked questions
What's the difference between oral and IV nicardipine?
They are different products. Oral capsules treat chronic stable angina and ongoing hypertension over the long term. IV nicardipine is used only in a monitored clinical setting for short-term blood pressure control when oral treatment isn't feasible, such as during a hypertensive emergency, with a plan to switch back to oral therapy once possible. (1) (2)
Is nicardipine safe while breastfeeding?
Sources genuinely disagree. The FDA prescribing label advises against breastfeeding while taking nicardipine. The NIH's LactMed database, looking at similar milk-level data, concludes the amount an infant would ingest is small and not expected to cause problems, and lists nifedipine as an alternative some clinicians may prefer. Discuss this directly with your prescriber and your baby's healthcare provider rather than relying on one source alone. (1) (3)
Can I stop taking nicardipine suddenly?
No — do not stop without consulting your prescriber. If you're also taking a beta-blocker, that needs a gradual taper too, since nicardipine does not protect against beta-blocker withdrawal effects. (1) (2)
Does nicardipine need a lower dose if I have liver or kidney problems?
Often yes. Severe liver disease roughly quadruples total drug exposure and greatly extends how long it stays in your body, so a lower starting dose (20 mg twice daily) with careful titration is recommended. Mild kidney impairment roughly doubles drug levels, so careful, gradual dose titration is advised. Your prescriber will individualize this. (1)
What is the mechanism of action of nicardipine?
Nicardipine is a dihydropyridine calcium channel blocker, more selective for vascular smooth muscle than cardiac muscle. Oral: ~35% bioavailability (saturable first-pass hepatic metabolism), >95% protein-bound, hepatically metabolized via CYP2C8/2D6/3A4, terminal half-life averaging 8.6 hours, steady state in 2-3 days with TID dosing. IV: triphasic decline (alpha ~3 min, beta ~45 min, gamma/terminal ~14 hours), clearance 0.4 L/hr/kg, volume of distribution 8.3 L/kg, linear PK over 0.5-40 mg/hr, steady state approached at 24-48 hours. (1) (2)
References
- Nicardipine Hydrochloride Capsules 20 mg and 30 mg — prescribing informationDailyMed / FDA (Epic Pharma, LLC label) · United States · accessed 2026-07-27 · source 1
- Nicardipine Hydrochloride Injection, for intravenous use — prescribing informationDailyMed / FDA · United States · accessed 2026-07-27 · source 2
- Nicardipine (LactMed entry LM408)LactMed, NICHD / NCBI Bookshelf · United States · accessed 2026-07-27 · source 3
- Nicardipine Hydrochloride — substance search resultMHRA Products (products.mhra.gov.uk) · United Kingdom · accessed 2026-07-27 · source 4
- Nicardipine (Mercury Pharma)Healthdirect Australia · Australia · accessed 2026-07-27 · source 5
- Cardene 20mg capsules — DIN 02162741Health Canada Drug Product Database (via secondary aggregator report) · Canada · accessed 2026-07-27 · source 6
- Cardene Injection (nicardipine hydrochloride 2.5 mg/mL) regulatory historyHealth Canada (via secondary regulatory-history report) · Canada · accessed 2026-07-27 · source 7
- Regulatory Decision Summary for Vlexio (nicardipine hydrochloride solution)Health Canada, Drug and Health Products Portal · Canada · accessed 2026-07-27 · source 8
- Listing of intravenous nicardipinePharmac (New Zealand) · New Zealand · accessed 2026-07-27 · source 9
- Calcium Channel BlockersStatPearls, NCBI Bookshelf · class_level_not_country_specific · accessed 2026-07-27 · source 10
Brand names by country
Single-ingredient nicardipine names are shown separately by country. Product availability, strengths, and supply rules can change; combination products are not included here.
Priority countries
United States
- Cardene IV.2 mg/mL, .1 mg/mL, 2.5 mg0mL · baxter healthcare corporation