How do beta-blockers work in the body?

Beta-blockers function by blocking the effects of adrenaline, also known as epinephrine, on beta-adrenergic receptors found in various tissues, including the heart, lungs, and blood vessels. By inhibiting adrenaline binding to these receptors, beta-blockers reduce heart rate, decrease force of contraction, and lower blood pressure. This makes them effective in treating conditions such as hypertension, heart failure, arrhythmias, and anxiety.

In contrast, enhancing the action of adrenaline or stimulating beta-adrenergic receptors would lead to increased heart rate and blood pressure, which is contrary to the therapeutic effects of beta-blockers. Thus, the primary action of beta-blockers is to antagonize the effects of adrenaline, leading to a calming effect on the cardiovascular system and improving outcomes in various cardiovascular diseases.