What Is Amlodipine Besylate?

Myocardial and smooth muscle contraction depends on extracellular calcium ions entering the cell through specific ion channels. Amlodipine besylate is a dihydropyridine calcium antagonist (calcium antagonist or slow channel blocker). This product selectively inhibits calcium ions from entering the smooth muscle cells and cardiomyocytes across the membrane, and has a greater effect on smooth muscle than the heart muscle.

Amlodipine

Drug name : Amlodipine besylate Generic name : Amlodipine besylate [National Medical Insurance Catalogue B].

Alias : Amorodipine, Norvasc.

English : AMLODIPINE BESYLATE.

Chinese chemical name : 3-ethyl-5-methyl-2- (2-aminoethoxymethyl) -4- (2-chlorophenyl) -1,4-dihydro-6-methyl-3, 5-pyridine dicarboxylate benzenesulfonate.

Molecular formula : C ₂₀ H ₂₅ ClN ₂ O ₅ · C ₆ H ₆ O ₃ S

Molecular weight : 567.1

CAS number : 111470-99-6

Solubility : soluble in methanol, slightly soluble in water.

This product belongs to the third generation calcium antagonist.

Instructions for Amlodipine Besylate Tablets

Drug Name

Common name: Amlodipine besylate tablets.

English name: Amlodipine Besylate Tablets

Chinese Pinyin: Benhuangsuan Anlüdiping Pian

The main ingredient of this product is amlodipine besylate, and its chemical name is: 3-ethyl-5-methyl-2- (2-aminoethoxylate)

Methyl) -4- (2-chlorophenyl) -1,4-dihydro-6-methyl-3,5-pyridinedicarboxylate benzenesulfonate.

Its structural formula is:

Molecular formula: C20H25ClN2O5 · C6H6O3S

Molecular weight: 567.06

[Character]

This product is white or off-white film.

[Pharmacology and Toxicology]

Amlodipine is a calcium channel blocker (that is, a slow channel blocker or calcium ion antagonist), which blocks calcium ion transmembrane

Into myocardial and vascular smooth muscle cells.

The mechanism of amlodipine's antihypertensive effect is the direct relaxation of vascular smooth muscle. The exact mechanism to relieve angina is not yet complete

Sure, but it can reduce total peripheral vascular resistance and relieve coronary spasm by dilating the peripheral arterioles and coronary arteries.

Contractures, reduce the heart's afterload, reduce heart energy expenditure and need for oxygen, thereby alleviating angina.

Pharmacokinetics

Amlodipine is well absorbed orally and is not affected by food intake. The blood concentration reached a peak 6-12 hours after the administration, the absolute bioavailability was about 64-80%, the apparent distribution volume was about 21L / kg, and the terminal elimination half-life was about 35-50 hours, once a day. After 7-8 days of continuous administration, the blood drug concentration reaches a steady state. Amlodipine is extensively metabolized by the liver into inactive metabolites. 10% of the original drug and 60% of the metabolites are excreted from the urine, and the plasma protein binds The rate is about 97.5%.

[Indications]

1. Hypertension. This product can be used alone or in combination with other antihypertensive drugs.

2. Chronic stable angina pectoris and variant angina pectoris. This product can be used alone or in combination with other anti-angina drugs.

Dosage

1. The initial dose for treating hypertension is 5 mg once daily and the maximum dose is 10 mg once daily. The initial dose of debilitated or elderly patients and patients with liver dysfunction is 2.5mg, once a day. This dose can also be the original dose of other antihypertensive drugs. Dose adjustments should be based on individual patient response. General dose adjustment should begin after 7-14 days. If clinically needed, after close observation of the patient, dose adjustment can be started more quickly.

2. The initial dose for angina pectoris is 5-10 mg once daily. Older patients and patients with liver dysfunction are advised to use lower doses. The effective dose for most people is 10 mg / day.

Adverse reactions

Amlodipine is well tolerated. The most common adverse events in placebo-controlled clinical trials for hypertension or angina pectoris were flushing, fatigue, edema, dizziness, headache, abdominal pain, nausea, palpitations, and lethargy. No significant clinical laboratory abnormalities associated with this product were found in these clinical trials.

Allergic reactions are rare and include pruritus, rash, angioedema, and erythema polymorpha.

Similar to other calcium antagonists, the following adverse events have been reported rarely, but the events are difficult to distinguish from the natural course of underlying diseases, such as myocardial infarction, arrhythmia (including bradycardia, ventricular tachycardia, and atrial fibrillation) And chest pain.

[Taboo]

Patients who are allergic to dihydropyridines or any of the ingredients in this product are contraindicated.

Precautions

1. Warning: Very few patients, especially those with severe coronary obstructive disease, experience increased frequency, prolonged and / or worsening of angina pectoris, or acute myocardial infarction when they start calcium antagonist therapy or increase their dose. The mechanism of action is unclear.

2. Because the vasodilator effect of this product is gradually produced, the occurrence of acute hypotension after taking this product is rarely reported. However, in patients with severe aortic stenosis, caution should be exercised when combined with other peripheral vasodilators.

3 Use in patients with heart failure: Caution should be used in patients with congestive heart failure. In a long-term, placebo-controlled study (PRAISE-2) in patients with non-ischemic heart failure (NYHA3 III-IV), although the incidence of exacerbation of heart failure was not significantly different from placebo, it was compared with ammonia. An increase in lodipine-related pulmonary edema has been reported.

4 Use in patients with impaired liver function: Like all other calcium antagonists, the half-life of this product is extended when liver function is impaired. However, the corresponding recommended dose has not been determined, therefore, this product should be used with caution.

5. Use in patients with renal failure: changes in the blood concentration of amlodipine have no correlation with the degree of renal impairment. Therefore, normal doses can be used. This product cannot be removed by dialysis.

[Medication for pregnant and lactating women]

There is no corresponding research data on pregnant women's medication, so this product can only be used in pregnant women when very necessary.

It is unknown whether this product can be secreted by breast milk. Breastfeeding women taking medication should discontinue breastfeeding.

[Child medication]

There is no information on the use of this product in children.

[Medication for elderly patients]

The peak time of the blood concentration of this product is similar in elderly and young patients. The increase in the area under the drug-time curve (AUC) and the extension of the elimination half-life in elderly patients tend to reduce the elimination rate. Elderly patients have been reported to be as well tolerated as younger patients when receiving similar doses of amlodipine. Therefore, normal doses can be used in elderly patients. However, it is appropriate to start with a smaller dose and gradually increase it.

medicine interactions

The combination of this product with the following drugs is safe: thiazide diuretics, -adrenergic receptor blockers, -adrenergic receptor blockers, angiotensin converting enzyme inhibitors, long-acting nitric acid Ester drugs, sublingual nitroglycerin, non-steroidal anti-inflammatory drugs, antibiotics and oral hypoglycemic agents.

Data from in vitro studies using human plasma show that this product does not affect the plasma protein binding rate of digoxin, phenytoin, warfarin, or indomethacin.

Effects of other drugs on amlodipine:

Cimetidine: Combination with Cimetidine does not change the pharmacokinetics of amlodipine.

Grapefruit juice: 20 healthy volunteers took 240ml grapefruit juice and 10mg amlodipine at the same time. No significant effect on the pharmacokinetics of amlodipine was seen.

Aluminum / magnesium (antacid): Taking aluminum / magnesium antacid and a single dose of amlodipine at the same time, no significant effect on the pharmacokinetics 4 of amlodipine was seen.

Sildenafil (Silenafil): A single dose of 100 mg sildenafil does not affect the pharmacokinetics of amlodipine in patients with essential hypertension. Combination of two drugs, each drug independently exerts its antihypertensive effect.

Effects of Amlodipine on Other Drugs: Atorvastatin: When 10 mg amlodipine and 80 mg atorvastatin are used simultaneously, the steady-state pharmacokinetic parameters of atorvastatin have not changed significantly.

Digoxin: Combination of amlodipine and digoxin did not change plasma digoxin concentration or renal clearance in normal volunteers.

Ethanol (alcohol): Single or multiple doses of 10 mg amlodipine have no effect on the pharmacokinetics of ethanol.

Warfarin: The combination of amlodipine and warfarin does not change the prothrombin reaction time of warfarin.

Cyclosporine: Pharmacokinetic studies show that amlodipine does not significantly change the pharmacokinetics of cyclosporin.

Drug / laboratory interaction: unknown.

[Drug overdose]

The available data suggest that severe overdose can lead to excessive dilation of peripheral blood vessels, followed by significant and persistent systemic hypotension.

Use this product in excess to wash the stomach. When significant hypotension is caused, active cardiovascular support treatment is required, including cardiopulmonary function monitoring, extremity elevation, and attention to circulating blood volume and urine volume. To restore vascular tone and blood pressure, vasoconstrictors can also be used when there are no contraindications. Intravenous injection of calcium gluconate is also beneficial in reversing the effects of calcium antagonists. Due to the high binding rate of this product to plasma proteins, dialysis treatment is not beneficial.

specification

2.5mg / 5mg / 10mg.

Storage

Shade, sealed and stored in a cool place.

package

Packed in aluminum-plastic board. 7 pcs / board × 1 / box; 7 pcs / board × 2 / box; 7 pcs / board × 4 / box.

[Validity Period]

Tentatively set for two years.

Approval Number

2.5mg Chinese Medicine Standard H20031087

5mg Chinese Medicine Standard H20020390

10mg Chinese Medicine Standard H20031088