Hypercor 2.5 Mechanism of Action

Pharmacology: Pharmacodynamics: Bisoprolol is a β₁-selective adrenergic blocking agent which does not exhibit the intrinsic sympathomimetic activity or the membrane stabilizing activity. According to in vitro studies at low dosages, Bisoprolol selectively inhibits response to adrenergic stimuli by competitively blocking cardiac β₁-adrenergic receptors, while having little effect on the β₂-adrenergic receptors of bronchial and vascular smooth muscle but at high doses (e.g., 20 mg or higher), the selectivity of Bisoprolol on β₁-adrenergic receptors usually diminishes, and the drug will competitively inhibit both β₁ and β₂-adrenergic receptors.
Pharmacokinetics: Absorption: Bisoprolol is almost completely absorbed from the gastrointestinal tract and undergoes only minimal first-pass metabolism resulting in an oral bioavailability of about 90%. Peak plasma concentrations occur 2 to 4 hours after oral doses.
Distribution: Bisoprolol is about 30% bound to plasma proteins.
Metabolism: Bisoprolol is moderately lipid soluble. It is metabolised in the liver.
Excretion: Bisoprolol has a plasma elimination half-life of 10 to 12 hours and is excreted in urine, about 50% as unchanged drug and 50% as metabolites.