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Amlodipine (norvasc®) 

Adult (usual) Angina: 5-10 mg po qd.
Hypertension initial: 5 mg po qd; maintenance 5-10 mg po qd.
FDA labeled indications: Angina, stable or unstable; Hypertension. Small, fragile, or elderly individuals, or patients with hepatic insufficiency may be started on 2.5 mg once daily and this dose may be used when adding Norvasc® to other antihypertensive therapy.

Titration: In general, titration should proceed over 7 to 14 days so that the physician can fully assess the patient's response to each dose level.
[Supplied:  2.5, 5, 10mg tab]

Studies in Patients with Congestive Heart Failure:

Study: (PRAISE-2) randomized patients with NYHA class III (80%) or IV (20%) heart failure without clinical symptoms or objective evidence of underlying ischemic disease, on stable doses of ACE inhibitor (99%), digitalis (99%) and diuretics (99%), to placebo (n=827) or NORVASC (n=827) and followed them for a mean of 33 months. There was no statistically significant difference between NORVASC and placebo in the primary endpoint of all cause mortality (95% confidence limits from 8% reduction to 29% increase on NORVASC). With NORVASC there were more reports of pulmonary edema.

Bepridil  (vascor®)

Dosing: Adults: Oral: Initial: 200 mg/day, then adjust dose at 10-day intervals until optimal response is achieved; usual dose: 300 mg/day; maximum daily dose: 400 mg
Dosage adjustment in renal impairment: Risk of toxic reactions is greater in patients with renal impairment; dose selection should be cautious, usually starting at the low end of the dosage range

Elderly: Peak concentrations and half-life are markedly increased in the elderly (>74 years); dose selection should be cautious, usually starting at the low end of the dosage range
Supplied
Tablet, as hydrochloride: 200 mg, 300 mg

Clevidipine -cleviprex ®

INDICATIONS AND USAGE
Cleviprex is a dihydropyridine calcium channel blocker indicated for the reduction of blood pressure when oral therapy is not feasible or not desirable.

DRUG INTERACTIONS
At clinically relevant concentrations, clevidipine and its metabolites do not inhibit or induce any CYP450 enzymes. The potential of clevidipine to interact with other drugs is low

USE IN SPECIFIC POPULATIONS
Pediatric use: Safety and effectiveness of Cleviprex in children under 18 years of age have not been established.

DOSAGE AND ADMINISTRATION
For intravenous use: Cleviprex is intended for intravenous use. Titrate Cleviprex to achieve the desired blood pressure reduction. Individualize dosage depending on the blood pressure response of the patient and the goal blood pressure.

Monitoring: Monitor blood pressure and heart rate during infusion, and until vital signs stabilize.

Initial dose: Initiate intravenous infusion of Cleviprex at 1-2 mg/hour.

Dose titration: Double the dose at short (90 second) intervals initially. As the blood pressure approaches goal, increase the dose by less than doubling and lengthen the time between dose adjustments to every 5-10 minutes. An approximately 1-2 mg/hour increase will generally produce an additional 2-4 mmHg decrease in systolic pressure.

Maintenance dose: Most patients will achieve the desired therapeutic response at approximately 4-6 mg/hour. Severe hypertension is likely to require higher doses.

Maximum dose: Most patients have received maximum doses of 16 mg/hour or less. There is limited experience with short-term dosing as high as 32 mg/hour. Because of lipid load restrictions, no more than 1000 mL or an average of 21 mg/hour of Cleviprex infusion is recommended per 24-hour period. There is little experience beyond 72 hours at any dose.

Transition to an oral antihypertensive agent: Discontinue Cleviprex or titrate downward while appropriate oral therapy is established. When an oral antihypertensive agent is being instituted, consider the lag time of onset of the oral agent’s effect. Continue blood pressure monitoring until desired effect is achieved.

Special populations: Special populations were not specifically studied. In clinical trials, 78 patients with abnormal hepatic function (one or more of the following: elevated serum bilirubin, AST/SGOT, ALT/SGPT) and 121 patients with moderate to severe renal impairment were treated with Cleviprex. An initial Cleviprex infusion rate of 1-2 mg/hour is appropriate in these patients.

Table 1 is a guideline for dosing conversion from mg/hour to mL/hour.

Table 1. Dose conversion
Dose
(mg/hour)
Dose
(mL/hour)
1 2
2 4
4 8
6 12
8 16
10 20
12 24
14 28
16 32
18 36
20 40
22 44
24 48
26 52
28 56
30 60
32 64

Instructions for Administration
Maintain aseptic technique while handling Cleviprex. Cleviprex is a single-use parenteral product. Do not use if contamination is suspected. Once the stopper is punctured, use within 12 hours and discard any unused portion.

Cleviprex is supplied in sterile, pre-mixed, ready-to-use 50 mL or 100 mL vials. Invert vial gently several times before use to ensure uniformity of the emulsion prior to administration. Inspect parenteral drug products for particulate matter and discoloration prior to administration whenever solution and container permit. Administer Cleviprex using an infusion device allowing calibrated infusion rates. Commercially available standard plastic cannulae may be used to administer the infusion. Administer Cleviprex by a central line or a peripheral line.

Cleviprex should not be administered in the same line as other medications.

Cleviprex should not be diluted, but it can be administered with the following

  • Water for Injection, USP
  • Sodium Chloride (0.9%) Injection, USP
  • Dextrose (5%) Injection, USP
  • Dextrose (5%) in Sodium Chloride (0.9%) Injection, USP
  • Dextrose (5%) in Ringers Lactate Injection, USP
  • Lactated Ringers Injection, USP
  • 10% amino acid

HOW SUPPLIED
Cleviprex is a sterile, milky white injectable emulsion for intravenous use, available in the following two configurations:

50 mL single-use vial with 0.5 mg/mL clevidipine
100 mL single-use vial with 0.5 mg/mL clevidipine

Diltiazem (cardizem ®) 

Adult (usual) Oral:
Angina
: (regular release tablets) initial 30 mg po qid; usual dose 180-360 mg po daily (maximum 360 mg daily). Angina: (extended release capsule; Dilacor(R) XR), initial 120 mg po qd; usual dose 120-480 mg once daily, maximum 540 mg/day. Hypertension: (Cardizem SR), initial 60-120 mg po q12h.; usual dose 120-180 mg bid, maximum 360 mg/day. Hypertension: ( Dilacor(R) XR): initial, 120-240 mg orally once daily; titrate after 14 days; usual dose, 240-360 mg orally once daily, maximum 540 mg/day.

Arrhythmia: (IV bolus), initial 0.25 mg/kg (or 20 mg) IV over 2 minutes; if inadequate response, may give second bolus 0.35 mg/kg (25 mg) after 15 min Arrhythmia: (IV continuous infusion), initial 5-10 mg/hr; increase in 5 mg/hr increments up to 15 mg/hr maintained for up to 24 hr.

Higher doses - Continuous infusion ??:

Crit Care Med. 2001 Jun;29(6):1149-53. Amiodarone versus diltiazem for rate control in critically ill patients with atrial tachyarrhythmias.
Group 1 received diltiazem in a 25-mg bolus followed by a continuous infusion of 20 mg/hr for 24 hrs, group 2 received amiodarone in a 300-mg bolus, and group 3 received amiodarone in a 300-mg bolus followed by 45 mg/hr for 24 hrs. CONCLUSION: Sufficient rate control can be achieved in critically ill patients with atrial tachyarrhythmias using either diltiazem or amiodarone. Although diltiazem allowed for significantly better 24-hr heart rate control, this effect was offset by a significantly higher incidence of hypotension requiring discontinuation of the drug. Amiodarone may be an alternative in patients with severe hemodynamic compromise.

Conversion from I.V. diltiazem to oral diltiazem: Start oral approximately 3 hours after bolus dose. Oral dose (mg/day) is approximately equal to [rate (mg/hour) x 3 + 3] x 10.
5 mg/hour = 180 mg/day;
7 mg/hour = 240 mg/day
11 mg/hour = 360 mg/day

[Supplied: Immediate release tablets: 30, 60, 90, 120 mg. Sustained released capsules (SR): 60, 90, 120mg. Extended release capsules (CD): 120,180,240,300,360 mg. Vials (IV): 25, 50, 125 mg (5 mg/ml) ]

Felodipine (plendil®) 

CLINICAL PHARMACOLOGY - Mechanism of Action
Felodipine is a member of the dihydropyridine class of calcium channel antagonists (calcium channel blockers). It reversibly competes with nitrendipine and/or other calcium channel blockers for dihydropyridine binding sites, blocks voltage-dependent Ca++ currents in vascular smooth muscle and cultured rabbit atrial cells, and blocks potassium-induced contracture of the rat portal vein.

In vitro studies show that the effects of felodipine on contractile processes are selective, with greater effects on vascular smooth muscle than cardiac muscle. Negative inotropic effects can be detected in vitro, but such effects have not been seen in intact animals.

The effect of felodipine on blood pressure is principally a consequence of a dose-related decrease of peripheral vascular resistance in man, with a modest reflex increase in heart rate. With the exception of a mild diuretic effect seen in several animal species and man, the effects of felodipine are accounted for by its effects on peripheral vascular resistance.

Administration: avoid taking with grapefruit juice. Dose adjustments should be made at intervals of not less than 2 weeks.  o not crush or chew extended release tablets; swallow whole.

Dosage
Adults:  hypertension: Oral: 2.5-10 mg once daily; usual initial dose: 5 mg; increase by 5 mg at 2-week intervals, as needed; maximum: 10 mg
Usual dose range (JNC 7) for hypertension: 2.5-20 mg once daily
Elderly: Begin with 2.5 mg/day
Dosing adjustment/comments in hepatic impairment: Initial: 2.5 mg/day; monitor blood pressure

[Supplied   2.5 mg, 5 mg, 10 mg ER tab]

Isradipine (dynacirc®) 

CLINICAL PHARMACOLOGY
Mechanism of Action
Isradipine is a dihydropyridine calcium channel blocker. It binds to calcium channels with high affinity and specificity and inhibits calcium flux into cardiac and smooth muscle. The effects observed in mechanistic experiments in vitro and studied in intact animals and man are compatible with this mechanism of action and are typical of the class.

Except for diuretic activity, the mechanism of which is not clearly understood, the pharmacodynamic effects of isradipine observed in whole animals can also be explained by calcium channel blocking activity, especially dilating effects in arterioles which reduce systemic resistance and lower blood pressure, with a small increase in resting heart rate. Although like other dihydropyridine calcium channel blockers, isradipine has negative inotropic effects in vitro, studies conducted in intact anesthetized animals have shown that the vasodilating effect occurs at doses lower than those which affect contractility. In patients with normal ventricular function, isradipine’s afterload reducing properties lead to some increase in cardiac output.

Effects in patients with impaired ventricular function have not been fully studied.

Clinical Effects
Dose-related reductions in supine and standing blood pressure are achieved within 2-3 hours following single oral doses of 2.5 mg, 5 mg, 10 mg, and 20 mg DynaCirc® (isradipine), with a duration of action (at least 50% of peak response) of more than 12 hours following administration of the highest dose.

DynaCirc® (isradipine) has been shown in controlled, double-blind clinical trials to be an effective antihypertensive agent when used as monotherapy, or when added to therapy with thiazide-type diuretics. During chronic administration, divided doses (b.i.d.) in the range of 5-20 mg daily have been shown to be effective, with response at trough (prior to next dose) over 50% of the peak blood pressure effect. The response is dose-related between 5-10 mg daily. DynaCirc® (isradipine) is equally effective in reducing supine, sitting, and standing blood pressure.

On chronic administration, increases in resting pulse rate averaged about 3-5 beats/min. These increases were not dose-related.

Dosing: Hypertension:
Oral: Adults: 2.5 mg twice daily; antihypertensive response occurs in 2-3 hours; maximal response in 2-4 weeks; increase dose at 2- to 4-week intervals at 2.5-5 mg increments; usual dose range (JNC 7): 2.5-10 mg/day in 2 divided doses. Note: Most patients show no improvement with doses >10 mg/day except adverse reaction rate increases; therefore, maximal dose in older adults should be 10 mg/day.

Supplied
Capsule (DynaCirc®): 2.5 mg, 5 mg
Tablet, controlled release (DynaCirc® CR): 5 mg, 10 mg

Nicardipine (cardene®) 

Clinical Pharmacology-  MECHANISM OF ACTION
Nicardipine inhibits the transmembrane influx of calcium ions into cardiac muscle and smooth muscle without changing serum calcium concentrations. The contractile processes of cardiac muscle and vascular smooth muscle are dependent upon the movement of extracellular calcium ions into these cells through specific ion channels. The effects of nicardipine are more selective to vascular smooth muscle than cardiac muscle. In animal models, nicardipine produced relaxation of coronary vascular smooth muscle at drug levels which cause little or no negative inotropic effect

Dosage Adults:
Oral:
Immediate release: Initial: 20 mg 3 times/day; usual: 20-40 mg 3 times/day (allow 3 days between dose increases).
Sustained release: Initial: 30 mg twice daily, titrate up to 60 mg twice daily.

Note: The total daily dose of immediate-release product may not automatically be equivalent to the daily sustained-release dose; use caution in converting.

 I.V. (dilute to 0.1 mg/mL):
Acute hypertension: Initial: 5 mg/hour increased by 2.5 mg/hour every 15 minutes to a maximum of 15 mg/hour; consider reduction to 3 mg/hour after response is achieved. Monitor and titrate to lowest dose necessary to maintain stable blood pressure.

Substitution for oral therapy (approximate equivalents):
20 mg every 8 hours oral, equivalent to 0.5 mg/hour I.V. infusion
30 mg every 8 hours oral, equivalent to 1.2 mg/hour I.V. infusion
40 mg every 8 hours oral, equivalent to 2.2 mg/hour I.V. infusion

Dosing adjustment in renal impairment: Titrate dose beginning with 20 mg 3 times/day (immediate release) or 30 mg twice daily (sustained release). Specific guidelines for adjustment of I.V. nicardipine are not available, but careful monitoring/adjustment is warranted.

Dosing adjustment in hepatic impairment: Starting dose: 20 mg twice daily (immediate release) with titration. Specific guidelines for adjustment of I.V. nicardipine are not available, but careful monitoring/adjustment is warranted.

Supplied
Capsule (Cardene®): 20 mg, 30 mg
Capsule, sustained release (Cardene® SR): 30 mg, 45 mg, 60 mg
Injection, solution (Cardene® IV): 2.5 mg/mL (10 mL)

Nifedipine (procardia®) 

WARNING
The use of sublingual short-acting nifedipine in hypertensive emergencies and pseudoemergencies is neither safe nor effective and SHOULD BE ABANDONED! Serious adverse events (cerebrovascular ischemia, syncope, heart block, stroke, sinus arrest, severe hypotension, acute myocardial infarction, ECG changes, and fetal distress) have been reported in relation to such use.

CLINICAL PHARMACOLOGY
Nifedipine is a calcium ion influx inhibitor (slow-channel blocker or calcium ion antagonist) which inhibits the transmembrane influx of calcium ions into vascular smooth muscle and cardiac muscle. The contractile processes of vascular smooth muscle and cardiac muscle are dependent upon the movement of extracellular calcium ions into these cells through specific ion channels. Nifedipine selectively inhibits calcium ion influx across the cell membrane of vascular smooth muscle and cardiac muscle without altering serum calcium concentrations.

Mechanism of Action:
The mechanism by which nifedipine reduces arterial blood pressure involves peripheral arterial vasodilatation and, consequently, a reduction in peripheral vascular resistance. The increased peripheral vascular resistance that is an underlying cause of hypertension results from an increase in active tension in the vascular smooth muscle. Studies have demonstrated that the increase in active tension reflects an increase in cytosolic free calcium.

Nifedipine is a peripheral arterial vasodilator which acts directly on vascular smooth muscle. The binding of nifedipine to voltage-dependent and possibly receptor-operated channels in vascular smooth muscle results in an inhibition of calcium influx through these channels. Stores of intracellular calcium in vascular smooth muscle are limited and thus dependent upon the influx of extracellular calcium for contraction to occur. The reduction in calcium influx by nifedipine causes arterial vasodilation and decreased peripheral vascular resistance which results in reduced arterial blood pressure.

Dosing:  Oral:
Adolescents and Adults: ( Note: When switching from immediate release to sustained release formulations, total daily dose will start the same)

Initial: 30 mg once daily as sustained release formulation, or if indicated, 10 mg 3 times/day as capsules
Usual dose: 10-30 mg 3 times/day as capsules or 30-60 mg once daily as sustained release
Maximum dose: 120-180 mg/day

Increase sustained release at 7- to 14-day intervals

Dosing adjustment in hepatic impairment: Reduce oral dose by 50% to 60% in patients with cirrhosis.

Supplied
Capsule, liquid-filled: 10 mg, 20 mg
Tablet, extended release: 30 mg, 60 mg, 90 mg
Adalat® CC, Nifediac™ CC, Procardia XL®: 30 mg, 60 mg, 90 mg
Afeditab™, Nifedical™ XL: 30 mg, 60 mg

 nimodipine 

Drug UPDATES: Nimodipine capsule
[Drug information  /  PDF]  
Dosing:  Click (+) next to Dosage and Administration section (drug info link)

Initial U.S. Approval:  2013

Mechanism of Action:
Nimodipine is a calcium channel blocker. The contractile processes of smooth muscle cells are dependent upon calcium ions, which enter these cells during depolarization as slow ionic transmembrane currents. Nimodipine inhibits calcium ion transfer into these cells and thus inhibits contractions of vascular smooth muscle. In animal experiments, nimodipine had a greater effect on cerebral arteries than on arteries elsewhere in the body perhaps because it is highly lipophilic, allowing it to cross the blood-brain barrier; concentrations of nimodipine as high as 12.5 ng/mL have been detected in the cerebrospinal fluid of nimodipine-treated subarachnoid hemorrhage (SAH) patients.

The precise mechanism of action of nimodipine in humans is unknown. Although the clinical studies described below demonstrate a favorable effect of nimodipine on the severity of neurological deficits caused by cerebral vasospasm following SAH, there is no arteriographic evidence that the drug either prevents or relieves the spasm of these arteries. However, whether or not the arteriographic methodology utilized was adequate to detect a clinically meaningful effect, if any, on vasospasm is unknown.

INDICATIONS AND USAGE:  Nimodipine is indicated for the improvement of neurological outcome by reducing the incidence and severity of ischemic deficits in patients with subarachnoid hemorrhage from ruptured intracranial berry aneurysms regardless of their post-ictus neurological condition (i.e., Hunt and Hess Grades I-V).

HOW SUPPLIED: Nimodipine capsules 30 mg are clear yellow solution filled in oblong opaque light yellow softgel capsules, imprinted “135” in black ink. The capsules are available as follows:

NDC 57664-135-64 Unit Dose Blisters of 30 (6 x 5)
NDC 57664-135-65 Unit Dose Blisters of 100 (4 x 25)

Storage: The capsules should be stored in manufacturer's original foil package at 20° to 25°C (68° to 77°F) [see USP Controlled Room Temperature].

Capsules should be protected from light and freezing.

-----------------
Drug UPDATES: NYMALIZE ® (nimodipine) oral solution Initial U.S. Approval: 1988
[Drug information  /  PDF]  
Dosing:  Click (+) next to Dosage and Administration section (drug info link)

Initial U.S. Approval:  2013

INDICATIONS AND USAGE:  NYMALIZE is a dihydropyridine calcium channel blocker indicated for the improvement of neurological outcome by reducing the incidence and severity of ischemic deficits in adult patients with subarachnoid hemorrhage (SAH) from ruptured intracranial berry aneurysms regardless of their post-ictus neurological condition (i.e., Hunt and Hess Grades I-V).

DOSAGE AND ADMINISTRATION
2.1 Administration Instructions
Administer only enterally (e.g., oral, nasogastric tube, or gastric tube route). Do not administer intravenously or by other parenteral routes. For all routes of administration, begin NYMALIZE within 96 hours of the onset of SAH. Administer one hour before a meal or two hours after a meal for all routes of administration [see Clinical Pharmacology (12.3)].

2.2 Administration by Oral Route
The recommended oral dosage is 20 mL (60 mg) every 4 hours for 21 consecutive days.

2.3 Administration Via Nasogastric or Gastric Tube
Using the supplied oral syringe labeled "ORAL USE ONLY", administer 20 mL (60 mg) every 4 hours into a nasogastric or gastric tube for 21 consecutive days. For each dose, refill the syringe with 20 mL of 0.9% saline solution and then flush any remaining contents from nasogastric or gastric tube into the stomach.

2.4 Dosage Adjustments in Patients with Cirrhosis
In patients with cirrhosis, reduce the dosage to 10 mL (30 mg) every 4 hours [see Warnings and Precautions (5.2), Clinical Pharmacology (12.3)].

HOW SUPPLIED:Oral Solution: 60 mg per 20 mL (3 mg/mL), pale yellow solution

Nisoldipine (sular®) 

CLINICAL PHARMACOLOGY
Mechanism of Action
Nisoldipine is a member of the dihydropyridine class of calcium channel antagonists (calcium ion antagonists or slow channel blockers) that inhibit the transmembrane influx of calcium into vascular smooth muscle and cardiac muscle. It reversibly competes with other dihydropyridines for binding to the calcium channel. Because the contractile process of vascular smooth muscle is dependent upon the movement of extracellular calcium into the muscle through specific ion channels, inhibition of the calcium channel results in dilation of the arterioles. In vitro studies show that the effects of nisoldipine on contractile processes are selective, with greater potency on vascular smooth muscle than on cardiac muscle. Although, like other dihydropyridine calcium channel blockers, nisoldipine has negative inotropic effects in vitro, studies conducted in intact anesthetized animals have shown that the vasodilating effect occurs as doses lower than those that affect cardiac contractility.

The effect of nisoldipine on blood pressure is principally a consequence of a dose-related decrease of peripheral vascular resistance. While nisoldipine, like other dihydropyridines, exhibits a mild diuretic effect, most of the antihypertensive activity is attributed to its effect on peripheral vascular resistance.

Adults: Oral: Initial: 20 mg once daily, then increase by 10 mg/week (or longer intervals) to attain adequate control of blood pressure; usual dose range (JNC 7): 10-40 mg once daily; doses >60 mg once daily are not recommended. A starting dose not exceeding 10 mg/day is recommended for the elderly and those with hepatic impairment.

Supplied
Tablet, extended release: 10 mg, 20 mg, 30 mg, 40 mg

Verapamil  (isoptin ® )

Adult (usual):
Angina: (extended-release) initial: 180 mg po qd at bedtime. Titrate up to 480 mg at bedtime- maximum 540 mg at bedtime. (immediate release) initial: 80 mg po tid - may titrate at daily or weekly intervals to 360 mg daily.
Arrhythmias, supraventricular: (immediate-release) initial: 240-320 mg po daily in 3-4 divided doses. Non-digitalized patients may require up to 480 mg daily in 3-4 divided doses. Arrhythmias, supraventricular: 5-10 mg IV (0.075-0.15 mg/kg) IV bolus over 2 min. May give additional 10 mg after 30 minutes if no response.
Hypertension: (extended-release) initial, 180 mg tablet po qd at bedtime OR 200 mg capsule po qd at bedtime. Maintenance: titrate up to 480 mg TAB qd at hs or 400 mg capsule po qd at hs.
Hypertension: (immediate-release) initial- 80 mg po tid. May titrate at daily or weekly intervals to 360-480 mg daily. Hypertension: (sustained-release) initial: 240 mg orally once daily in the morning. Maintenance (based on response): titrate up to 240 mg bid (tablet) or 480 mg (capsule) once a day in the morning.
Migraine headache, prophylaxis: 80 mg po 3-4 times daily.

[Supplied:
Immediate release tablet: 40, 80, 120mg.
Sustained release tablets (SR): 120, 180, 240 mg.
Sustained released capsules (Verelan): 120,180,240,360mg.
Covera HS (extended release tab): 180,240mg.
Verelan PM (ER cap): 100,200,300mg. ]
-----------------------------------

Dosing (Adults)
Angina: Oral: Initial: 80-120 mg twice daily (elderly or small stature: 40 mg twice
daily); range: 240-480 mg/day in 3-4 divided doses

Hypertension: Oral:
Immediate release: 80 mg 3 times/day; usual dose range (JNC 7): 80-320 mg/day in 2 divided doses.
Sustained release: 240 mg/day; usual dose range (JNC 7): 120-360 mg/day in 1-2 divided doses; 120 mg/day in the elderly or small patients (no evidence of additional benefit in doses >360 mg/day).
Extended release:
Covera-HS®: Usual dose range (JNC 7): 120-360 mg once daily (once-daily dosing is recommended at bedtime)
Verelan® PM: Usual dose range: 200-400 mg once daily at bedtime

Arrhythmia (SVT): I.V.: 2.5-5 mg (over 2 minutes); second dose of 5-10 mg (~0.15 mg/kg) may be given 15-30 minutes after the initial dose if patient tolerates, but does not respond to initial dose; maximum total dose: 20 mg

Reference(s)

National Institutes of Health, U.S. National Library of Medicine, DailyMed Database.
Provides access to the latest drug monographs submitted to the Food and Drug Administration (FDA). Please review the latest applicable package insert for additional information and possible updates.  A local search option of this data can be found here.

Calcium Channel Blockers