AEMCA Practice Exam

Which of the following is a selective beta-2 adrenergic agonist?

1. Propranolol

2. Salbutamol

3. Metoprolol

4. Amiodarone

The correct answer is: Salbutamol

Salbutamol is a selective beta-2 adrenergic agonist primarily used in the management of asthma and chronic obstructive pulmonary disease (COPD). Its primary action is to relax bronchial smooth muscle, leading to bronchodilation, which helps alleviate symptoms of airway constriction. Salbutamol specifically targets the beta-2 receptors located in the lungs, distinguishing it from other medications in the options provided. For example, propranolol is a non-selective beta blocker that affects both beta-1 and beta-2 receptors, while metoprolol is a selective beta-1 blocker primarily affecting the heart. Amiodarone is an antiarrhythmic medication that does not primarily interact with adrenergic receptors. The specificity of salbutamol for beta-2 receptors makes it particularly effective for respiratory issues without significantly impacting heart rate or blood pressure, unlike the other drugs listed.