From the Guidelines
Carvedilol (Coreg) and Amlodipine have distinct mechanisms of action: Carvedilol is a beta-blocker that acts by inhibiting the adverse effects of the sympathetic nervous system, whereas Amlodipine is a calcium channel blocker that reduces peripheral vasoconstriction and left ventricular afterload.
Mechanism of Action
- Carvedilol: blocks alpha-1–, beta-1–, and beta-2–adrenergic receptors, antagonizing the deleterious effects of sympathetic activation, such as increased ventricular volumes and pressure, cardiac hypertrophy, and myocardial ischemia 1.
- Amlodipine: has greater selectivity for calcium channels in vascular smooth muscle cells, reducing peripheral vasoconstriction and left ventricular afterload, making it useful for treating hypertension in patients with elevated blood pressure despite optimization of guideline-directed medical therapy (GDMT) 1.
Key Differences
- Carvedilol has a more comprehensive mechanism of action, targeting both alpha-1 and beta-adrenergic receptors, whereas Amlodipine primarily affects calcium channels in vascular smooth muscle cells.
- The use of Carvedilol is supported by evidence showing reduced mortality in patients with chronic heart failure, particularly when used at target doses (25 mg twice daily) 1.
- Amlodipine may be used for treatment of hypertension, but its role in heart failure management is more limited, with some studies suggesting potential benefits in specific subgroups, such as nonischemic cardiomyopathy 1.
From the FDA Drug Label
Carvedilol Tablet is a racemic mixture in which nonselective β-adrenoreceptor blocking activity is present in the S(-) enantiomer and α1-adrenergic blocking activity is present in both R(+) and S(-) enantiomers at equal potency.
Amlodipine is a dihydropyridine calcium antagonist (calcium ion antagonist or slow-channel blocker) that inhibits the transmembrane influx of calcium ions into vascular smooth muscle and cardiac muscle.
The mechanism of action for:
- Carvedilol (Coreg) is through nonselective β-adrenoreceptor blocking activity and α1-adrenergic blocking activity.
- Amlodipine is through inhibition of calcium ion influx into vascular smooth muscle and cardiac muscle, acting as a peripheral arterial vasodilator. 2 3
From the Research
Mechanism of Action for Carvedilol (Coreg)
- Carvedilol is a dual-acting drug that produces two complementary effects: beta-blockade and vasodilation 4, 5, 6.
- The vasodilation is mediated predominantly by specific alpha 1-adrenoceptor blockade 4, 6.
- Carvedilol also has calcium channel antagonist properties at higher concentrations, which may contribute to its antihypertensive activity 6.
- The beta-blocking activity of carvedilol reduces regional and systemic vascular resistance in various experimental models, healthy volunteers, and patients with cardiovascular diseases 4, 5.
Mechanism of Action for Amlodipine
- There is no direct information provided about the mechanism of action of Amlodipine in the given studies.
- However, it is mentioned that Amlodipine is a calcium channel blocker, and its efficacy is compared with Carvedilol in some studies 5, 7.
Comparison of Mechanisms of Action
- Carvedilol and Amlodipine have different primary mechanisms of action, with Carvedilol being a beta-blocker and alpha 1-adrenoceptor antagonist, and Amlodipine being a calcium channel blocker 5, 7.
- Both drugs have been shown to be effective in reducing blood pressure and improving symptoms in patients with hypertension and angina 5, 7.