Product Overview
[Drug Name]
Generic Name: Levoamlodipine Besylate Tablets
Trade Name: Shimeilijian Levoamlodipine Besylate Tablets 2.5mg*14 Tablets
Pinyin Full Code: ShiMeiLiJian BenHuangSuanZuoAnLvDiPingPian 2.5mg*14Pian
[Main Ingredients]
The main ingredient of this product is levamlodipine besylate.
[Properties]
This product is a white tablet.
[Indications/Main Functions]
(1) Hypertension (used alone or in combination with other drugs); (2) Angina pectoris: especially spontaneous angina pectoris (used alone or in combination with other drugs).
[Precautions]
1. Use in patients with impaired liver function. As with all other calcium antagonists, this product should be used with extreme caution when the liver function is impaired. 2. Use in patients with renal failure. Patients with renal impairment can use normal doses. 3. This product cannot be dialyzed.
[Drug Interactions]
Contraindicated in patients allergic to dihydropyridine calcium channel blockers.
[Pediatric Use]
There are no data on the use of this product in children.
[Elderly Use]
Elderly patients can use the normal dose. However, it is advisable to start with a lower dose and then gradually increase the dose.
[Pregnant and Breastfeeding Use]
This product is recommended only when there are no safer alternatives or when the disease itself poses a greater risk to the mother and child.
[Specifications]
2.5mg x 14 tablets (SmithRx)
[Dosage and Administration]
The usual starting dose is 5 mg orally once daily, with a maximum of 10 mg once daily. This product is not recommended for thin individuals, those with a weak constitution, the elderly, or those with liver dysfunction.
[Adverse Reactions]
This product is well tolerated by patients. (1) Less common side effects include headache, edema, fatigue, insomnia, heart and abdominal pain, flushing, palpitations and dizziness; (2) Very rare side effects include itching, rash, dyspnea, weakness, muscle cramps and indigestion; (3) Similar to other calcium channel blockers, there are very few reports of adverse reactions such as myocardial infarction and chest pain, and these adverse reactions cannot be clearly distinguished from the patient's underlying disease; (4) No abnormal laboratory test parameters related to this product have been found.
[Contraindications]
This product is contraindicated in patients who are allergic to dihydropyridine calcium channel blockers.
[Overdose]
(1) In case of overdose of this product, gastric lavage can be performed. (2) When significant hypotension occurs, active cardiovascular support treatment is required, including heart and lung function monitoring, limb elevation, and attention to circulation and urine output. (3) To restore vascular tone and blood pressure, vasoconstrictors can also be used in the absence of contraindications. (4) Intravenous calcium gluconate is also beneficial in reversing the effects of calcium channel blockers. (5) Since this product is highly bound to plasma proteins, dialysis treatment is ineffective in relieving drug overdose.
[Pharmacology and Toxicology]
(1) This product is a calcium influx blocker (also known as a calcium channel blocker or calcium ion antagonist), which blocks the entry of extracellular calcium ions into myocardial and vascular smooth muscle cells through the calcium ion channels (slow channels) in the cell membrane. (2) This product directly relaxes vascular smooth muscle and has an antihypertensive effect. (3) The mechanism of action of this product in relieving angina pectoris has not been fully determined, but it can reduce myocardial ischemia through the following effects: a) Dilate peripheral arterioles, reduce peripheral resistance (afterload), and thus reduce myocardial energy consumption and oxygen demand. b) Dilate coronary arteries and coronary arterioles in normal and ischemic areas, increasing myocardial oxygen supply in patients with coronary artery spasm (variant angina). (4) This product takes a long time to metabolize in the liver. Like all other calcium antagonists, it should be used with caution when liver function is impaired.
[Pharmacokinetics]
(1) According to literature reports, after oral administration of amlodipine besylate tablets, the plasma concentration reaches a peak 6-12 hours later, the absolute bioavailability is about 64-80%, the apparent distribution volume is about 21L/kg, and the terminal elimination half-life is about 35-50 hours. After 7-8 days of continuous administration once a day, the plasma concentration reaches a steady state. Amlodipine besylate is extensively metabolized by the liver into inactive metabolites, 10% of the parent drug and 60% of the metabolites are excreted in the urine, and the plasma protein binding rate is about 97.5%. (2) According to literature reports, 18 healthy volunteers took 20 mg of racemic amlodipine orally once, and the average peak plasma concentration ratio of pharmacologically active levoamlodipine to inactive dextroamlodipine was 47:53, and the average AUC ratio was 41:49. The mean terminal elimination half-life of levoamlodipine was 49.6 hours, and that of dextroamlodipine was 34.9 hours. The terminal elimination half-life of amlodipine was significantly correlated with the half-life of levoamlodipine.
