Amlodine HD Mechanism of Action

Pharmacology: Pharmacokinetics: Amlodipine is well absorbed following oral administration with peak blood concentrations occurring after 6 to 12 hours. The bioavailability is about 60 to 65%. Amlodipine is reported to be about 97.5% bound to plasma proteins. It has a prolonged terminal elimination half-life of 35 to 50 hours and steady-state plasma concentrations are not achieved until after 7 to 8 days of administration. Amlodipine is extensively metabolised in the liver; metabolites are mostly excreted in urine together with less than 10% of a dose as unchanged drug.
Atorvastatin is rapidly absorbed from the gastrointestinal tract. It has low absolute bioavailability of about 12% due to presystemic clearance in the gastrointestinal mucosa and/or first-pass metabolism in the liver, its primary site of action. Atorvastatin is metabolized by the cytochrome P450 isoenzyme CYP3A4 to a number of compounds which are also active inhibitors of HMG-CoA reductase. The mean plasma elimination half-life of atorvastatin is about 14 hours although the half-life of inhibitory activity for HMG-CoA reductase is approximately 20 to 30 hours due to the contribution of the active metabolites. It is 98% bound to plasma proteins. Atorvastatin is excreted as metabolites, primarily in the bile.