Final answer:
The most likely adverse effect in a patient taking a beta-adrenergic blocking agent is bradycardia, which is a slowing down of the heart rate. Beta-blockers work by blocking the action of adrenaline on the heart, preventing tachycardia but potentially leading to an excessively slow heart rate if overprescribed.
Step-by-step explanation:
The most likely adverse effect in a patient taking a beta-adrenergic blocking agent is bradycardia. Beta-adrenergic blocking agents, often referred to as β-blockers, are medications that reduce the stimulatory effects of adrenaline on the heart. They primarily work by binding to the beta-1 receptors on heart muscles, effectively blocking the action of neurotransmitters like norepinephrine (NE) and adrenaline, which would typically increase heart rate (HR) and blood pressure.
These drugs are commonly prescribed for conditions such as hypertension and congestive heart failure and are known to slow HR as part of their action. If these drugs are prescribed in excess, they may lead to bradycardia, which is an abnormally slow heart rate. This is in contrast to tachycardia, which is a rapid heart rate that β-blockers are used to treat.