A 32-year-old woman with persistent asthma is started on inhaled corticosteroid therapy. Which is the most common adverse effect of regular inhaled corticosteroid use?

Explanation

## Most Common Adverse Effect of Inhaled Corticosteroids ### Overview Inhaled corticosteroids (ICS) are the first-line anti-inflammatory agents in persistent asthma. While generally safe due to minimal systemic absorption, local adverse effects are common. ### Oral Candidiasis — The Most Common Local Effect **Key Point:** Oral candidiasis (thrush) is the most frequent adverse effect of ICS, occurring in 5–10% of users depending on dose and technique. **Mechanism:** - ICS deposit on oropharyngeal mucosa - Suppresses local immune response and alters oral flora - Candida albicans overgrowth → pseudomembranous plaques, erythema, dysphagia **Prevention & Management:** 1. Rinse mouth with water immediately after each dose 2. Use a spacer device to reduce oropharyngeal deposition 3. If candidiasis develops: topical antifungal (miconazole, clotrimazole) or oral fluconazole ### Why Other Options Are Incorrect | Adverse Effect | Frequency | Context | |---|---|---| | **Systemic corticosteroid toxicity** | Rare with ICS alone | Occurs only at very high doses (>2000 mcg/day) or with poor inhaler technique; minimal systemic absorption at standard doses | | **Acute bronchospasm** | Rare | Paradoxical bronchoconstriction can occur but is uncommon; more associated with LABA monotherapy | | **Vocal cord paralysis** | Extremely rare | Hoarseness may occur (dysphonia), but permanent paralysis is not a recognized ICS effect | **High-Yield:** Dysphonia (hoarseness) is the second most common local effect (~5–10%), but candidiasis remains the most frequent. **Clinical Pearl:** Patients should be counseled on proper inhaler technique and mouth rinsing at the time of ICS initiation to minimize candidiasis risk. [cite:Harrison 21e Ch 297]