NICARDIPINE HYDROCHLORIDE
Brand names: Nicardipine Hydrochloride, NICARDIPINE HYDROCHLORIDE, Nicardipine hydrochloride, nicardipine hydrochloride, CARDENE IV, Nicardipine Hydrochloride in Sodium Chloride, Cardene IV
Warnings
WARNINGS Increased Angina About 7% of patients in short-term, placebo-controlled angina trials have developed increased frequency, duration or severity of angina on starting nicardipine hydrochloride capsules or at the time of dosage increases, compared with 4% of patients on placebo. Comparisons with beta-blockers also show a greater frequency of increased angina, 4% vs 1%. The mechanism of this effect has not been established (see ADVERSE REACTIONS ). Use in Patients With Congestive Heart Failure Although preliminary hemodynamic studies in patients with congestive heart failure have shown that nicardipine hydrochloride capsules reduced afterload without impairing myocardial contractility, it has a negative inotropic effect in vitro and in some patients. Caution should be exercised when using the drug in congestive heart failure patients, particularly in combination with a beta-blocker. Beta-Blocker Withdrawal Nicardipine hydrochloride capsules are not a beta-blocker and therefore gives no protection against the dangers of abrupt beta-blocker withdrawal; any such withdrawal should be by gradual reduction of the dose of beta-blocker, preferably over 8 to 10 days.
Contraindications
CONTRAINDICATIONS Nicardipine hydrochloride capsules are contraindicated in patients with hypersensitivity to the drug. Because part of the effect of nicardipine hydrochloride capsules are secondary to reduced afterload, the drug is also contraindicated in patients with advanced aortic stenosis. Reduction of diastolic pressure in these patients may worsen rather than improve myocardial oxygen balance.
Overdose
OVERDOSAGE Overdosage with a 600-mg single dose (15 to 30 times normal clinical dose) has been reported. Marked hypotension (blood pressure unobtainable) and bradycardia (heart rate 20 bpm in normal sinus rhythm) occurred, along with drowsiness, confusion and slurred speech. Supportive treatment with a vasopressor resulted in gradual improvement with normal vital signs approximately 9 hours posttreatment. Based on results obtained in laboratory animals, overdosage may cause systemic hypotension, bradycardia (following initial tachycardia) and progressive atrioventricular conduction block. Reversible hepatic function abnormalities and sporadic focal hepatic necrosis were noted in some animal species receiving very large doses of nicardipine. For treatment of overdose standard measures (for example, evacuation of gastric contents, elevation of extremities, attention to circulating fluid volume, and urine output) including monitoring of cardiac and respiratory functions should be implemented. The patient should be positioned so as to avoid cerebral anoxia. Frequent blood pressure determinations are essential. Vasopressors are clinically indicated for patients exhibiting profound hypotension. Intravenous calcium gluconate may help reverse the effects of calcium entry blockade.
Drug interactions
Drug Interactions Beta Blockers In controlled clinical studies, adrenergic beta-receptor blockers have been frequently administered concomitantly with nicardipine hydrochloride capsules. The combination is well tolerated. Cimetidine Cimetidine increases nicardipine hydrochloride capsules plasma levels. Patients receiving the two drugs concomitantly should be carefully monitored. Digoxin Some calcium blockers may increase the concentration of digitalis preparations in the blood. Nicardipine hydrochloride capsules usually do not alter the plasma levels of digoxin; however, serum digoxin levels should be evaluated after concomitant therapy with nicardipine hydrochloride capsules are initiated. Maalox® Coadministration of Maalox TC had no effect on nicardipine hydrochloride capsules absorption. Fentanyl Anesthesia Severe hypotension has been reported during fentanyl anesthesia with concomitant use of a beta-blocker and a calcium channel blocker. Even though such interactions were not seen during clinical studies with nicardipine hydrochloride capsules, an increased volume of circulating fluids might be required if such an interaction were to occur. Cyclosporine Concomitant administration of oral or intravenous nicardipine and cyclosporine results in elevated plasma cyclosporine levels through nicardipine inhibition of hepatic microsomal enzymes, including CYP3A4. Plasma concentrations of cyclosporine should therefore be closely monitored, and its dosage reduced accordingly, in patients treated with nicardipine. Tacrolimus: Concomitant administration of oral or intravenous nicardipine and tacrolimus may result in elevated plasma tacrolimus levels through nicardipine inhibition of hepatic microsomal enzymes, including CYP3A4. Closely monitor plasma concentrations of tacrolimus during nicardipine administration, and adjust the dose of tacrolimus accordingly. When therapeutic concentrations of furosemide, propranolol, dipyridamole, warfarin, quinidine or naproxen were added to human plasma (in vitro), the plasma protein binding of nicardipine hydrochloride capsules were not altered. Carcinogenesis, Mutagenesis, Impairment of Fertility Rats treated with nicardipine in the diet (at concentrations calculated to provide daily dosage levels of 5, 15 or 45 mg/kg/day) for 2 years showed a dose-dependent increase in thyroid hyperplasia and neoplasia (follicular adenoma/carcinoma). One- and 3 month studies in the rat have suggested that these results are linked to a nicardipine-induced reduction in plasma thyroxine (T4) levels with a consequent increase in plasma levels of thyroid stimulating hormone (TSH). Chronic elevation of TSH is known to cause hyperstimulation of the thyroid. In rats on an iodine deficient diet, nicardipine administration for 1 month was associated with thyroid hyperplasia that was prevented by T4 supplementation. Mice treated with nicardipine in the diet (at concentrations calculated to provide daily dosage levels of up to 100 mg/kg/day) for up to 18 months showed no evidence of neoplasia of any tissue and no evidence of thyroid changes. There was no evidence of thyroid pathology in dogs treated with up to 25 mg nicardipine/kg/day for 1 year and no evidence of effects of nicardipine on thyroid function (plasma T4 and TSH) in man. There was no evidence of a mutagenic potential of nicardipine in a battery of genotoxicity tests conducted on microbial indicator organisms, in micronucleus tests in mice and hamsters, or in a sister chromatid exchange study in hamsters. No impairment of fertility was seen in male or female rats administered nicardipine at oral doses as high as 100 mg/kg/day (50 times the 40 mg tid maximum recommended antianginal or antihypertensive dose in man, assuming a patient weight of 60 kg). Pregnancy Nicardipine was embryocidal when administered orally to pregnant Japanese White rabbits, during organogenesis, at 150 mg/kg/day (a dose associated with marked body weight gain suppression in the treated doe) but not at 50 mg/kg/day (25 times the maximum recommended antianginal or antihypertensive dose in man). No adverse effects on the fetus were observed when New Zealand albino rabbits were treated, during organogenesis, with up to 100 mg nicardipine/kg/day (a dose associated with significant mortality in the treated doe). In pregnant rats administered nicardipine orally at up to 100 mg/kg/day (50 times the maximum recommended human dose) there was no evidence of embryolethality or teratogenicity. However, dystocia, reduced birth weights, reduced neonatal survival, and reduced neonatal weight gain were noted. There are no adequate and well-controlled studies in pregnant women. Nicardipine hydrochloride capsules should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus. Nursing Mothers Studies in rats have shown significant concentrations of nicardipine in maternal milk following oral administration. For this reason it is recommended that women who wish to breastfeed should not take this drug. Pediatric Use Safety and efficacy in patients under the age of 18 have not been established. Geriatric Use Pharmacokinetic parameters did not differ between elderly hypertensive patients (≥65 years) and healthy controls after 1 week of nicardipine hydrochloride capsules treatment at 20 mg tid. Plasma nicardipine hydrochloride capsules concentrations in elderly hypertensive subjects were similar to plasma concentrations in healthy young adult subjects when nicardipine hydrochloride capsules were administered at doses of 10, 20, and 30 mg tid, suggesting that the pharmacokinetics of nicardipine hydrochloride capsules are similar in young and elderly hypertensive patients. Clinical studies of nicardipine did not include sufficient numbers of subjects aged 65 and over to determine whether they respond differently from younger subjects. Other reported clinical experience has not identified differences in responses between the elderly and younger patients. In general, dose selection for an elderly patient should be cautious, usually starting at the low end of the dosing range, reflecting the greater frequency of decreased hepatic, renal, or cardiac function, and of concomitant disease or other drug therapy.
Uses
INDICATIONS AND USAGE I. Stable Angina Nicardipine hydrochloride capsules are indicated for the management of patients with chronic stable angina (effort-associated angina). Nicardipine hydrochloride capsules may be used alone or in combination with beta-blockers. II. Hypertension Nicardipine hydrochloride capsules are indicated for the treatment of hypertension. Nicardipine hydrochloride capsules may be used alone or in combination with other antihypertensive drugs. In administering nicardipine hydrochloride it is important to be aware of the relatively large peak to trough differences in blood pressure effect (See DOSAGE AND ADMINISTRATION ).
Dosage forms & strengths
DOSAGE AND ADMINISTRATION Angina The dose should be individually titrated for each patient beginning with 20 mg three times daily. Doses in the range of 20 to 40 mg three times a day have been shown to be effective. At least 3 days should be allowed before increasing the nicardipine hydrochloride capsules dose to ensure achievement of steady-state plasma drug concentrations. Concomitant Use With Other Antianginal Agents Sublingual NTG may be taken as required to abort acute anginal attacks during nicardipine hydrochloride capsules therapy. Prophylactic Nitrate Therapy : nicardipine hydrochloride capsules may be safely co-administered with short- and long-acting nitrates. Beta-blockers : Nicardipine hydrochloride capsules may be safely co-administered with beta- blockers (see Drug Interactions ) . Hypertension The dose of nicardipine hydrochloride capsules should be individually adjusted according to the blood pressure response beginning with 20 mg three times daily. The effective doses in clinical trials have ranged from 20 mg to 40 mg three times daily. The maximum blood pressure lowering effect occurs approximately 1 to 2 hours after dosing. To assess the adequacy of blood pressure response, the blood pressure should be measured at trough (8 hours after dosing). Because of the prominent peak effects of nicardipine, blood pressure should be measured 1 to 2 hours after dosing, particularly during initiation of therapy (see PRECAUTIONS: Blood Pressure , INDICATIONS AND USAGE , CLINICAL PHARMACOLOGY, Effects in Hypertension ). At least 3 days should be allowed before increasing the nicardipine hydrochloride capsules dose to ensure achievement of steady-state plasma drug concentrations. Concomitant Use With Other Antihypertensive Agents Diuretics : nicardipine hydrochloride capsules may be safety co-administered with thiazide diuretics. Beta-blockers : nicardipine hydrochloride capsules may be safely co-administered with beta-blocker (see PRECAUTIONS , Drug Interactions ) Special Patient Population Renal Insufficiency Although there is no evidence that nicardipine hydrochloride capsules impair renal function, careful dose titration beginning with 20 mg tid is advised (see PRECAUTIONS ). Hepatic Insufficiency Nicardipine hydrochloride capsules should be administered cautiously in patients with severely impaired hepatic function. A suggested starting dose of 20 mg twice a day is advised with individual titration based on clinical findings maintaining the twice a day schedule (see PRECAUTIONS ). Congestive Heart Failure Caution is advised when titrating nicardipine hydrochloride capsules dosage in patients with congestive heart failure (see WARNINGS ).