Bisosten Mechanism of Action

Pharmacology: Bisoprolol is a potent, highly β1-selective adrenoreceptor blocking agent devoid of intrinsic sympathomimetic activity and without relevant membrane stabilising activity.
As with other β1-blocking agents, the mode of action in hypertension is not clear but it is known that bisoprolol markedly depresses plasma renin levels.
In patients with angina, the blockade of β1-receptors reduces heart action and thus reduces oxygen demand. Hence, bisoprolol is effective in eliminating or reducing the symptoms.
Pharmacokinetics: 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 are reached 2 to 4 hours after oral doses. Bisoprolol is about 30% bound to plasma proteins. It has a plasma elimination half-life of 10 to 12 hours. Bisoprolol is moderately lipid-soluble. It is metabolized in the liver and excreted in urine, about 50% as unchanged drug and 50% as metabolites.