Amlodac

Amlodipine.

Each tablet of AMLODAC 5 contains: Amlodipine besilate equivalent to Amlodipine 5 mg.
Each tablet of AMLODAC 10 contains: Amlodipine besilate equivalent to Amlodipine 10 mg.

Pharmacology: Pharmacodynamics: Amlodipine is a calcium ion influx inhibitor (slow channel blocker or calcium ion antagonist) and inhibits the transmembrane influx of calcium ion into cardiac and vascular smooth muscle. The mechanism of the antihypertensive action of amlodipine is due to a direct relaxant effect on vascular smooth muscle. The precise mechanism by which amlodipine relieves angina has not been fully determined but amlodipine reduces total ischemic burden by the following two actions: 1. Amlodipine dilates peripheral arterioles and thus, reduces the total peripheral resistance against which the heart works. Since the heart rate remains stable, this unloading of the heart reduces myocardial energy consumption and oxygen requirements.
2. The mechanism of action of amlodipine also probably involves dilation of the main coronary arteries and coronary arterioles. The dilation increases myocardial oxygen in patients with coronary artery spasm (Prinzmetal's or variant angina) and blunts smoking induced coronary vasoconstriction.
Amlodipine has not been associated with any adverse metabolic effects or changes in plasma lipid.
Pharmacokinetics: After oral administration, amlodipine is well absorbed with peak blood levels between 6-12 hours post-dose. Absolute bioavailability has been estimated to be between 64 and 80%. The volume of distribution is approximately 21 L/Kg. In vitro studies have shown that approximately 97.5% of circulating amlodipine is bound to plasma protein.
Absorption of amlodipine is unaffected by food. The terminal plasma elimination half life is about 35-50 hours and is consistent with once daily dosing. Steady state plasma level are reached after 7-8 days of consecutive dosing. Amlodipine is extensively metabolized by the liver to inactive metabolites with 10% of the parent compound and 60% of metabolites excreted in urine. The time to reach peak plasma concentrations of amlodipine is similar in elderly and younger subjects. Amlodipine clearance tends to be decreased with resulting increases in AUC and elimination half life in patients with congestive heart failure were as expected for the patient age group studied.

First line treatment of hypertension and myocardial ischaemia associated with stable angina pectoris.

Amlodipine should be initiated at a dosage of 5 mg once daily which may be increased to a maximum dose of 10 mg once daily depending on the individual patient's response.

5 mg: Marked and probably prolonged systemic hypotension and bradycardia up to and including shock with fatal outcome have been reported. Gastric lavage or emetics may be worthwhile in some cases. Clinically significant hypotension due to amlodipine overdosage calls for active cardiovascular support including frequent monitoring of cardiac and respiratory function, elevation of extremities, and attention to circulating fluid volume and urine output. A vasoconstrictor may be helpful in restoring vascular tone and blood pressure.

Known sensitivity to dihydropyridines, amlodipine, or any of the inert ingredients.

Amlodipine should be used with caution in patients with impaired hepatic or renal function. Abrupt withdrawal of amlodipine may cause increased frequency and duration of chest pain. Amlodipine may cause a greater hypotensive and constipation effects in elderly than that seen in younger patients. Should not be administered during pregnancy or lactation.

5 mg: Safety of amlodipine in human pregnancy or lactation has not been established. Accordingly, use in pregnancy is only recommended when there is no safer alternative and when the disease itself carries greater risk for the mother and fetus.

Amlodipine is generally well tolerated. Very common side effects are oedema/peripheral oedema (5 mg) and flushing. Other adverse effects reported occasionally include muscle cramps, frequency of micturition/nocturia, coughing, dyspnea, impotence, visual disturbances, peripheral neuropathy, headache, dizziness, asthenia, nausea, tinnitus, taste perversion, skin discoloration, alopecia, hypotension, syncope and palpitations.
5 mg: Pulmonary oedema, fatigue, somnolence, abdominal pain, dyspepsia.

Amlodipine causes no change in digoxin's pharmacokinetics in healthy volunteers.
Cimetidine does not alter the kinetic profile of amlodipine.
No drug interaction occurs between amlodipine and nitroglycerin.
Azole antifungals (e.g. itraconazole, ketoconazole, fluconazole), erythromycin and CYP3A4 inhibitors inhibit metabolism of amlodipine.
Coadministration of grapefruit juice with amlodipine may increase serum levels of amlodipine.
Amlodipine should be used with caution when coadministered with sildenafil, tadalafil or vardenafil since blood pressure lowering effects of these drugs are additive with amlodipine.

Store below 30°C in a dry place. Protect from light.

Calcium Antagonists / Anti-Anginal Drugs

C08CA01 - amlodipine ; Belongs to the class of dihydropyridine derivative selective calcium-channel blockers with mainly vascular effects. Used in the treatment of cardiovascular diseases.

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