Verapamil Hydrochloride Tablets

1. Verapamil hydrochloride is a calcium ion antagonist. It exerts its pharmacological effects by regulating the influx of calcium ions on the cell membranes of myocardial conduction cells, myocardial contractile cells, and arterial smooth muscle cells, but does not change the serum calcium concentration. 2. Verapamil hydrochloride dilates the main coronary arteries and arterioles in normal and ischemic parts of the heart, antagonizes spontaneous or ergonovine-induced coronary artery spasm, increases the delivery of myocardial oxygen to patients with coronary artery spasm, relieves and prevents coronary artery spasm; Verapamil reduces total peripheral resistance and reduces myocardial oxygen consumption. It can be used to treat variant angina and unstable angina. 3. Verapamil reduces calcium ion influx, prolongs the effective refractory period of the atrioventricular node, slows conduction, and can reduce the ventricular rate of patients with chronic atrial fibrillation and atrial flutter; it reduces the frequency of paroxysmal supraventricular tachycardia. Verapamil usually does not affect the normal sinus rate, but can cause sinus arrest or sinoatrial block in patients with sick sinus syndrome; Verapamil does not change the action potential or intraventricular conduction time of the normal atrium, but it reduces the amplitude, speed and conduction speed of the depolarization of the inhibited atrial fibers, which may shorten the forward effective refractory period of the additional bypass channel, accelerate the ventricular rate of patients with atrioventricular bypass combined with atrial flutter or atrial fibrillation, and even induce ventricular fibrillation. 4 Verapamil produces a blood pressure-lowering effect by reducing the vascular resistance of the systemic circulation, and generally does not cause postural hypotension or reflex tachycardia. 5 Verapamil reduces afterload, inhibits myocardial contraction, and can improve left ventricular diastolic function. In isometric or dynamic myocardial exercise, verapamil does not change the cardiac contractile function of patients with normal ventricular function. In patients with organic heart disease, the negative inotropic effect of verapamil can be offset by the effect of reducing afterload, and the cardiac index does not decrease. However, patients with severe left ventricular dysfunction (e.g., pulmonary wedge pressure greater than 20 mmHg or ejection fraction less than 30%), or patients taking beta-blockers or other myocardial depressant drugs, may experience worsening of cardiac function. 6 Animal experiments suggest that the local anesthetic effect of verapamil is 1.6 times that of procaine equimolar. The effect and dosage in humans are still unclear. Carcinogenicity, mutagenicity and reproductive toxicity Verapamil is not carcinogenic. The Ames test confirmed that verapamil is not mutagenic. Long-term use of verapamil ge;30mg/Kg/d by Beagle dogs resulted in lens-shaped and/or suture-shaped changes, and ge;62.5mg/Kg/d caused cataracts with obvious symptoms. There have been no reports of cataract formation in humans due to verapamil. No impairment of fertility was observed in female mice. The effect on human fertility is still unclear.

The main ingredients and chemical names of this product are: ?-[3-[[2-(3,4-dimethoxyphenyl)ethyl]methylamino]propyl]-3,4-dimethoxy-?-isopropylphenylacetonitrile hydrochloride. Molecular formula: C27H38N2O4HCl Molecular weight: 491.07

This product is a sugar-coated tablet, which appears white after removing the sugar coating.

1. Angina pectoris: variant angina pectoris; unstable angina pectoris; chronic stable angina pectoris. 2. Arrhythmia: combined with digoxin to control the ventricular rate in chronic atrial fibrillation and/or atrial flutter; prevent recurrent paroxysmal supraventricular tachycardia. 3. Essential hypertension.

Individualized treatment is achieved by adjusting the dose. The safe and effective dose is no more than 480 mg/day. 1 Angina pectoris: The general dose is 80-120 mg/time of oral verapamil three times a day. The safe dose for patients with liver dysfunction and the elderly is 40 mg/time, three times a day. About 8 hours after taking the drug, decide whether to increase the dose based on the efficacy and safety assessment. 2 Arrhythmia: For patients with chronic atrial fibrillation taking digitalis, the total daily dose is 240-320 mg, taken orally three or four times a day. For the prevention of paroxysmal supraventricular tachycardia (patients not taking digitalis), the total daily dose for adults is 240-480 mg, taken orally three or four times a day. Age 1-5 years: daily dose 4-8 mg/kg, taken orally three times a day; or 40-80 mg taken orally every 8 hours. >5 years old: take 80 mg orally every 6-8 hours. 3 Primary hypertension: The general starting dose is 80 mg, taken orally, three times a day. The dosage can be up to 360-480 mg per day. For elderly people or those with small body types who respond to low doses, a starting dose of 40 mg orally three times a day should be considered.

Take the recommended single dose and daily total as the starting dose and gradually adjust the dose upward. Serious adverse reactions are rare. Adverse reactions with an incidence of 1-10%: constipation (7.3%); dizziness, mild headache (3.5%); nausea (2.7%); hypotension (2.5%); headache (2.2%). Peripheral edema (2.1%); congestive heart failure (1.8%); sinus bradycardia, I, II or III degree atrioventricular block; rash (1.2%); fatigue; palpitations; elevated transaminases, with or without elevated alkaline phosphatase and bilirubin, which is sometimes transient and may disappear even with continued use of verapamil. Adverse reactions with an incidence of less than 1%: hypotension; tachycardia; flushing; galactorrhea; gingival hyperplasia; non-obstructive paralytic ileus, etc.

1 Severe left ventricular dysfunction. 2 Hypotension (systolic blood pressure less than 90 mmHg) or cardiogenic shock. 3 Sick sinus syndrome (except patients with a pacemaker installed and functioning). 4 II or III degree atrioventricular block (except patients with a pacemaker installed and functioning). 5 Patients with atrial flutter or atrial fibrillation combined with atrioventricular bypass pathways. 6 Patients known to be allergic to verapamil hydrochloride.

Precautions for children: Safety and efficacy for children under 18 years of age have not been established. Precautions for pregnancy and lactation: Verapamil can cross the placenta. It should only be used in pregnant women who clearly need it and the benefits outweigh the risks to the fetus. Verapamil can be secreted into breast milk, and breastfeeding should be interrupted during the use of verapamil. Precautions for the elderly: The elimination half-life of elderly patients may be prolonged, and it must be considered that liver or kidney dysfunction is more common in the elderly. Generally, a lower starting dose should be used for the elderly.

1 Cytotoxic drugs such as cyclophosphamide, vincristine, procarbazine, prednisone, vinblastine, doxorubicin, and cisplatin reduce the absorption of verapamil. 2 Phenobarbital, hydantoin, vitamin D, sulfamethoxazole, and ramifen reduce the plasma concentration of verapamil by increasing liver metabolism. 3 Cimetidine may increase the bioavailability of verapamil. 4 Verapamil inhibits the elimination of ethanol, leading to increased ethanol concentration in the blood, which may prolong the toxic effects of alcohol. 5 A few cases reported that the combined use of verapamil and aspirin prolonged the bleeding time compared with aspirin alone. 6 Combined use with beta-receptor blockers can enhance the inhibitory effect on atrioventricular conduction. 7 Long-term use of verapamil increases the blood concentration of digoxin by 50-75%. Verapamil significantly affects the pharmacokinetics of digoxin in patients with cirrhosis, reducing the total clearance and extrarenal clearance of digoxin by 27% and 29%, respectively. Therefore, when taking verapamil, the doses of digoxin and digitalis must be reduced. 8 When used in combination with antihypertensive drugs such as vasodilators, angiotensin-converting enzyme inhibitors, and diuretics, the antihypertensive effects are superimposed, and patients receiving combined antihypertensive therapy should be appropriately monitored. 9 Combination with amiodarone may increase cardiac toxicity. 10 Patients with subaortic stenosis due to hypertrophic cardiomyopathy should avoid combined medication. 11 When verapamil is used in combination with flecainide, negative inotropic effects can be superimposed and atrioventricular conduction can be prolonged. 12 Verapamil can increase the blood concentrations of carbamazepine, cyclosporine, doxorubicin, and theophylline. 13 There are reports that verapamil increases patients' sensitivity to lithium (neurotoxicity). 14 Animal experiments suggest that when inhaled anesthetics are used simultaneously with verapamil, the doses of the two drugs need to be carefully adjusted to avoid excessive cardiac inhibition. 15 Avoid using verapamil and disopyramide simultaneously.

Keep sealed.

40mg

24 months

World Trade Tianjie Pharmaceutical (Jiangsu) Co., Ltd.

• Founded in:

  1979-11-20

• Address:

  North side of Haibin East Road, Fangqiang Farm, Dafeng District, Yancheng City

• Tax NO.:

  913209821407081740

• Registered Funds:

  30 million yuan

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