Why does a beta-2 adrenergic agonist inhaler relieve asthma symptoms during an attack?

💡 Explanation

Beta-2 adrenergic agonists stimulate beta-2 receptors on bronchial smooth muscle, causing bronchodilation through increased cAMP. Because of this smooth muscle relaxation, airway constriction reduces, therefore the inhaler's effects dominate rather than histamine's constricting influence, leading to symptom relief.

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