Amlokard Mechanism of Action

Pharmacology: Amlodipine besilate belongs to the 3rd generation dihydropyridine calcium-channel blockers. It primarily acts as a vasodilator, affecting slow L-type channels and has a greater selectivity for vascular smooth muscle as compared to the cardiac tissues.
It is a potent vasodilator with actions similar to other dihydropyridines. Only, amlodipine has smooth onset of effects and is longer lasting than other calcium blocking agents. Its actions are also found to be dependent on K⁺ concentration and thus, its effects are voltage dependent. Amlodipine exerts its peripheral and coronary vasodilating effect by interacting directly with both 1,4-dihydropyridine and diltiazem-binding sites on the calcium channel.
Pharmacokinetics: Amlodipine besilate is well absorbed upon oral administration. It reaches peak plasma concentration (C_max) after 6-12 hrs. C_max of the drug is not delayed by food. Its bioavailability is about 60-65%. Amlodipine besilate is reported to be about 97.5% bound to plasma protein with a volume of distribution of 21 L/kg.
Food does not affect the absorption of amlodipine.
It has a prolonged terminal elimination t_½ of approximately 35-50 hrs and achieves steady-state plasma concentration after 7-8 days of administration of Amlokard. Amlodipine besilate is mainly metabolized in the liver with its metabolites mostly excreted in the urine together with <10% of unchanged drug.
Amlodipine cannot be removed by dialysis.