Inhaled corticosteroids used in asthma management work primarily by which mechanism?

• A. Anti-inflammatory effect reducing airway edema and hyperresponsiveness.
• B. Bronchodilation through beta-adrenergic receptor stimulation.
• C. Inhibition of mucus production by goblet cells.
• D. Promotion of airway remodeling to widen bronchi.

Answer: (A)

Inhaled corticosteroids work primarily by dialing down the airway inflammation that drives asthma. They bind to glucocorticoid receptors in airway cells and alter gene transcription to reduce the production of inflammatory mediators like cytokines, chemokines, and adhesion molecules. This decreases the recruitment and activation of inflammatory cells (such as eosinophils and mast cells), lowers mucosal edema, and reduces airway hyperresponsiveness to triggers. Over time, this diminishes the frequency and severity of symptoms and exacerbations. This mechanism is different from bronchodilators, which relax airway smooth muscle to provide quick relief; it’s also not about goblet cell mucus production or promoting remodeling—corticosteroids aim to lessen chronic inflammation and its consequences.