What Is Amlodipine?

The chemical name of amlodipine is 6-methyl-2- (2-aminoethoxy) methyl-4- (2-chlorophenyl) -1,4-dihydro-3,5-pyridine di Methyl ethyl formate, yellow solid, molecular formula is C ₂₀ H ₂₅ ClN ₂ O ₅ , molecular weight is 408.87600, density is 1.227 g / cm3, melting point is 178-179ºC, boiling point is 527.2ºC at 760 mmHg.

Chinese name: Amlodipine
Foreign name: amlodipine

CAS number: 88150-42-9
Molecular formula: C20H25ClN2O5

Brief introduction of amlodipine compounds

Amlodipine Basic Information

Chinese name: amlodipine

Chinese alias: 6-methyl-2- (2-aminoethoxy) methyl-4- (2-chlorophenyl) -1,4-dihydro-3,5-pyridinedicarboxylic acid ethyl methyl ester; Clodipine; alodipine; amorodipine;

English name: amlodipine

English alias: Norvasc; Amlodipino; 3-ethyl 5-methyl () -2-[(2-aminoethoxy) methyl] -4- (2-chlorophenyl) -1,4-dihydro-6-methyl-3,5-pyridine dicarboxylate; Amlodipinum; 2-[(2-aminoethoxy) methyl] -4- (2-chlorophenyl) -1,4-dihydro-6-methyl-3,5-pyridinedicarboxylic acid 3-ethyl 5-methyl ester;

CAS number: 88150-42-9

Molecular formula: C ₂₀ H ₂₅ ClN ₂ O ₅

Molecular weight: 408.87600

Exact mass: 408.14500

PSA: 99.88000

LogP: 3.29540 ^[1]

Physical and Chemical Properties of Amlodipine

Appearance and properties: yellow solid

Density: 1.227 g / cm ³

Melting point: 178-179ºC

Boiling point: 527.2ºC at 760 mmHg

Storage conditions: -20ºC Freezer ^[1]

Amlodipine Compound Related Drugs

Amlodipine drug name

Amlodipine ^[2]

Amlodipine English name

Amlodipine ^[2]

Amlodipine

Luohuoxi; Amlodipine besylate; Anlodipine; Alodipine; Dihydropyridine sulfonate; Norvasc; Norvase; Amldipine Besylate ^[2]

Amlodipine classification

Circulatory Drugs> Antianginal Drugs> Ion Antagonists ^[2]

Amlodipine dosage form

Tablet: 2.5mg, 5mg, 10mg. ^[2]

Pharmacological effects of amlodipine

1. Dilate the peripheral arterioles to reduce peripheral resistance (postload), thereby reducing myocardial energy consumption and oxygen demand;

2. Dilate normal and ischemic coronary arteries and coronary arterioles, and increase myocardial oxygen supply in patients with coronary spasm (variant angina pectoris). ^[2]

Pharmacokinetics of Amlodipine

After 6 to 12 hours after oral administration, the blood concentration reached a peak, the serum half-life was 35 to 50 hours, and 97.5% bound to plasma proteins. Most of amlodipine is metabolized in the liver, excretion of the original drug is <10% (of which about 5% in urine), renal clearance is the main excretion pathway of metabolites (60%), and excretion is 20% to 25% with feces. Patient half-life can be as long as 60 hours. ^[2]

Indications for amlodipine

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

2. Chronic stable angina pectoris or vasospasm angina pectoris, can be used alone or in combination with other anti-angina pectoris drugs, such as nitrates and / or -blockers. ^[2]

Contraindications for Amlodipine

1. Allergy to amlodipine or other calcium channel blockers.

2. Severe hypotension. ^[2]

Amlodipine precautions

1. (1) Caution should be used in patients with aortic stenosis because the drug can cause blood pressure reduction; (2) Congestive heart failure, especially when combined with -blockers; (3) When liver function is impaired Drug metabolism decreases and half-life is prolonged, so it should be used with caution.

2. Amlodipine can be combined with other antihypertensive drugs such as thiazide diuretics, -blockers or angiotensin-converting enzyme inhibitors.

3. Amlodipine has no protective effect on the rebound phenomenon of withdrawal of drugs caused by the sudden withdrawal of -blockers. Discontinuation of -blockers should be slow.

4. The combination of nitroglycerin or long-acting nitrates with amlodipine can enhance the anti-anginal effect. Although no rebound phenomenon has been reported, the dose should be gradually reduced under the guidance of a physician when stopping the drug.

5. There is no need to stop medication before surgery, but the anesthesiologist must understand the patient's medication situation.

6. If a persistent skin reaction occurs after taking the drug, the drug should be discontinued.

7. Drug overdose and treatment: Overdose can cause significant and persistent peripheral vasodilation, leading to severe hypotension and reflex tachycardia. Bradycardia, or degree atrioventricular block, and cardiac arrest may also occur. Treatment: gastric lavage can be taken. Once overdose is found, heart and respiratory monitoring should be performed immediately, and blood pressure should be measured frequently. If hypotension occurs, extremities should be raised for fluid replacement. If there is still no response to the above conservative treatment, vasoconstrictor drugs (such as phenylephrine adrenaline, dopamine, norepinephrine adrenaline) can be given without contraindications, and pay close attention to circulation capacity and urine output . Intravenous administration of calcium gluconate may help reverse calcium channel blockade. If bradycardia occurs, atropine, isoprenaline and calcium chloride should be given, and a pacemaker should be placed if indicated. Because amlodipine is highly bound to plasma proteins, hemodialysis does not work. ^[2]

Amlodipine amlodipine adverse reactions

Have headache, mild to moderate edema, tiredness, nausea, flushing, palpitations and dizziness. ^[2]

Amlodipine amlodipine dosage

The initial 5mg each time, once a day, the maximum can be increased to 10mg each time, once a day. ^[2]

Interaction of amlodipine and amlodipine with other drugs

1. Combination with amiodarone can further inhibit sinus rhythm or aggravate atrioventricular block. Patients with sick sinus syndrome and incomplete atrioventricular block should avoid using both drugs together.

2. Combined with -blockers can effectively treat angina pectoris or hypertension, but the combination of dihydropyridine calcium channel blockers and -blockers may cause severe hypotension or bradycardia, It is more pronounced in patients with decreased left ventricular function, arrhythmias, or aortic stenosis. If a combination of two drugs is required, cardiac function should be carefully monitored, especially in patients with potential heart failure.

3. Saquinavir can inhibit cytochrome P ₄₅₀ 3A, reduce amlodipine metabolism, increase blood concentration, and increase toxicity.

4. When using fentanyl anesthesia, the combination of calcium channel blockers (including amlodipine) and -blockers can cause severe hypotension.

5. Delafield is an inhibitor of cytochrome P ₄₅₀ 3A4, which can reduce the metabolism of many dihydropyridine calcium channel blockers. If amlodipine is used in combination with it, it can cause an increase in plasma concentration and increased toxicity.

6. Quinopeptin / dafoputin can inhibit the metabolism of amlodipine via cytochrome P ₄₅₀ 3A4, enhance the toxicity of amlodipine, and reduce the amount if necessary.

7. Fluconazole, itraconazole, and ketoconazole can inhibit the cytochrome P ₄₅₀ 3A4 isoenzyme system related to the metabolism of dihydropyridine calcium channel blockers. Amlodipine, if used in combination with it, can increase blood drug concentration and increase adverse reactions.

8. Calcium channel blockers can enhance the hypotensive effect of buflomedil, and care should be taken when amlodipine is combined with buflomedil.

9. Amlodipine can increase the plasma concentration of cyclosporine, leading to increased toxicity of cyclosporine (such as renal failure, cholestasis, and paralysis). If combined, the blood concentration of cyclosporine should be monitored and the dosage adjusted accordingly.

10. With the use of lithium, it can cause neurotoxicity, nausea, vomiting, diarrhea, ataxia, tremor and / or numbness, so you must pay attention to it.

11. Combined with non-steroidal anti-inflammatory drugs and oral anticoagulants, it may increase gastrointestinal bleeding. Nonsteroidal anti-inflammatory drugs, especially indomethacin, can also reduce the antihypertensive effect of amlodipine, which may be due to inhibition of prostaglandin synthesis and / or cause water and sodium retention.

12. Nafcillin can induce the cytochrome P ₄₅₀ 3A enzyme system and reduce the efficacy of amlodipine.

13. Rifampicin can induce the metabolism of some calcium channel blockers. Although no interaction with amlodipine has been reported at present, the efficacy of amlodipine may decrease if used in combination.

14. Sympathomimetic amines can reduce the antihypertensive effect of amlodipine.

15. Use with estrogen can increase fluid retention and increase hypertension.

16. Ephedra contains ephedrine and pseudoephedrine, which has an uncertain effect on blood pressure in normal individuals and can reduce the efficacy of antihypertensive drugs. Patients with hypertension treated with amlodipine should avoid taking ephedra-containing preparations.

17. Sulpyridone can increase amlodipine protein binding and cause changes in plasma concentrations.

18. Amlodipine had no significant effect on renal clearance of digoxin and plasma concentration of digoxin.

19. Grapefruit juice can increase the blood concentration of amlodipine, so it should not be taken. The nutritional composition of orange juice is basically the same as that of grapefruit juice, but it has no effect on the metabolism of amlodipine, so you can take it. However, some studies have shown that drinking grapefruit juice at the same time has no significant effect on the pharmacokinetics of amlodipine. ^[2]

Amlodipine expert review

Amlodipine is a long-acting calcium antagonist that can be maintained once a day for 24 hours. The steady-state blood concentration is suitable for the treatment of hypertension and angina pectoris. It may be effective for CHF complicated by non-ischemic cardiomyopathy, but at present Not recommended yet. ^[2]