The Sound of Evolution
Carvedilol
Mechanism of action:
Carvedilol is a non-selective beta blocker with additional alpha1 receptor antagonistic activity, making it a third-generation beta blocker. Carvedilol blocks beta1 receptors in the heart, reducing heart rate and myocardial contractility, decreasing myocardial oxygen demand, and suppressing cardiac remodeling. It also blocks beta2 receptors in the bronchi and may therefore affect bronchial tone. At the same time, carvedilol blocks alpha1 receptors on vascular smooth muscle, inhibiting norepinephrine-induced vasoconstriction and causing vasodilation. Because the alpha1-blocking effect is greater than the beta2-blocking effect, the net result is peripheral vasodilation, reduced blood pressure, and decreased cardiac preload and afterload.
Reference(s):
1. Vanderhoff BT et al. (1998). Carvedilol: the new role of beta blockers in congestive heart failure. Am Fam Physician.
2. Oldham HG et al. (1997). In vitro identification of the human cytochrome P450 enzymes involved in the metabolism of R(+)- and S(-)-carvedilol. Drug Metab Dispos.
3. Takekuma Y et al. (2012). Mutual inhibition between carvedilol enantiomers during racemate glucuronidation mediated by human liver and intestinal microsomes. Biol Pharm Bull.