A 52-year-old male with moderate persistent asthma is started on inhaled corticosteroid therapy. Which is the most common adverse effect of inhaled corticosteroids that occurs in the oropharynx?

Explanation

## Oropharyngeal Adverse Effects of Inhaled Corticosteroids **Key Point:** Oral candidiasis (thrush) is the most common local adverse effect of inhaled corticosteroids, occurring in 5–10% of patients due to local immunosuppression and altered oropharyngeal flora. ### Mechanism of Oral Candidiasis with ICS 1. **Local immunosuppression:** Inhaled corticosteroids suppress local T-cell and neutrophil function in the oropharynx. 2. **Altered flora:** Reduction in normal bacterial flora allows overgrowth of *Candida albicans*. 3. **Deposition:** Direct deposition of ICS particles on oral mucosa creates a favorable microenvironment for fungal growth. 4. **Dose-dependent:** Risk increases with higher doses and longer duration of therapy. ### Prevention and Management | Strategy | Effectiveness | Notes | | --- | --- | --- | | **Spacer use** | High | Reduces oropharyngeal deposition by 70–90% | | **Mouth rinsing** | High | Rinse mouth with water after each inhalation | | **Gargling** | Moderate | Additional benefit if combined with rinsing | | **Lower ICS dose** | Variable | May compromise asthma control | | **Antifungal therapy** | High | Miconazole gel or nystatin suspension for active infection | **Clinical Pearl:** Patients should be counseled to rinse their mouth with water immediately after each ICS inhalation. This simple measure reduces candidiasis risk by >80%. **High-Yield:** The incidence of oral candidiasis is significantly lower with modern spacer devices and proper inhalation technique. Always ensure the patient uses a spacer and rinses mouth post-inhalation. **Mnemonic:** **RINSED** — Rinse mouth after Inhalation to Neutralize Steroid Effect and Decrease candidiasis. ### Why Other Options Are Incorrect - **Laryngeal edema:** Not a typical ICS adverse effect; more commonly associated with ACE inhibitors or anaphylaxis. - **Aphthous ulcers:** Not specifically linked to ICS use; more common in nutritional deficiencies or inflammatory bowel disease. - **Xerostomia:** Not a direct effect of ICS; may occur with systemic corticosteroids but not inhaled forms. **Warning:** Do not confuse oropharyngeal candidiasis (local, common) with systemic candidiasis (rare, requires immunocompromise). ICS cause only local candidiasis.