What treatment is recommended for a patient with rhinitis and cough caused by poor Air Quality Index (AQI)?

Treatment of Rhinitis and Cough from Poor Air Quality

For rhinitis and cough caused by poor air quality, initiate treatment with intranasal corticosteroids as first-line therapy, combined with oral second-generation antihistamines for sneezing and itching, while simultaneously implementing environmental exposure reduction strategies. 1

Initial Management Approach

Primary Pharmacologic Treatment

• Intranasal corticosteroids are the strongest recommendation for rhinitis symptoms affecting quality of life, regardless of whether the trigger is allergen-mediated or irritant-mediated from air pollution 1

• Oral second-generation antihistamines should be added if sneezing and itching are prominent complaints 1

• For persistent cough associated with upper airway symptoms, first-generation antihistamine/decongestant (A/D) combinations (such as dexbrompheniramine 6 mg or azatadine 1 mg with sustained-release pseudoephedrine 120 mg, both twice daily) have proven efficacy in treating chronic cough from upper airway cough syndrome 1

Critical Distinction in Antihistamine Selection

The evidence reveals an important nuance: first-generation antihistamines work better for non-allergic, irritant-induced rhinitis (like air pollution exposure) due to their anticholinergic properties, while second-generation antihistamines are more effective for allergic rhinitis 1. Since poor AQI typically causes irritant rhinitis rather than IgE-mediated allergic rhinitis, the first-generation A/D combination may be more effective for the cough component 1.

Environmental Exposure Reduction

• Identify and eliminate or reduce exposure to the environmental trigger - this is fundamental and should not be overlooked, as failure to address the source leads to increased medication requirements and potential disease progression 1

• Indoor air purification with HEPA filters significantly reduces particulate matter (PM2.5 by up to 51.8%) and decreases medication requirements in patients with rhinitis 2

• Advise avoidance of outdoor activities during high AQI periods and use of air filtration systems indoors 1, 3

Assessment for Comorbidities

Document and assess for associated conditions including asthma, conjunctivitis, and rhinosinusitis, as these commonly coexist with environmental rhinitis 1

• Air pollution exposure correlates with increased rhinitis severity and may trigger asthma exacerbations 4, 5

• Occupational and environmental exposure history must be obtained in all patients with chronic cough and rhinitis 1

Treatment Algorithm for Inadequate Response

If symptoms persist after 1-2 weeks of initial therapy:

1. Add combination therapy with intranasal antihistamines as an option for seasonal, perennial, or episodic rhinitis 1

2. Do NOT use oral leukotriene receptor antagonists as primary therapy - they are specifically not recommended for allergic rhinitis and have no established role in irritant rhinitis 1

3. For severe nasal obstruction with enlarged inferior turbinates failing medical management, consider referral for inferior turbinate reduction 1

4. Ipratropium bromide nasal spray may be effective when first-generation A/D preparations are contraindicated (e.g., glaucoma, symptomatic benign prostatic hypertrophy) 1

Important Caveats

• Newer generation antihistamines (terfenadine, loratadine) have been shown ineffective for treating cough associated with non-allergic rhinitis 1

• Improvement in cough typically occurs within days to 2 weeks of initiating appropriate therapy 1

• Rhinitis medicamentosa can develop from prolonged topical decongestant use - avoid long-term use of topical α-agonists like oxymetazoline 1

• Air pollution (particularly PM2.5, PM10, NO2) is associated with increased rhinitis severity, and patients without allergic sensitization may be more affected 4

Monitoring Response

• Clinical response should be evident within 2 weeks; if no improvement occurs, reassess the diagnosis and consider other causes of chronic cough (asthma, gastroesophageal reflux disease, non-asthmatic eosinophilic bronchitis) 1

• Fexofenadine specifically has evidence for improving allergic rhinitis symptoms aggravated by air pollution, though more efficacy studies are needed for other agents in this context 3