Pharmacology: Pharmacodynamics: Mechanism of Action: Amlodipine is a calcium channel blockers (slow channel blockers, calcium antagonist), share the ability to inhibit movement of calcium ions across the cell membrane. The effects on the cardiovascular system include depression of mechanical contraction of myocardial and smooth muscle and depression of both impulse formation (automaticity) and conduction velocity.
Pharmacokinetics: Following oral administration of amlodipine besylate, peak plasma concentrations of the drug are attained within 6-12 hours. Absolute bioavailability ranges from 64-90%; food does not affect bioavailability of amlodipine. Amlodipine is approximately 93% bound to plasma proteins. The drug is extensively (approximately 90%) metabolized to inactive metabolites in the liver. Amlodipine is excreted in the urine as metabolites (60%) and unchanged drug (10%). The terminal elimination half-life is about 30-50 hours.