What is the first-line treatment for upper airway cough syndrome?

First-Line Treatment for Upper Airway Cough Syndrome

First-generation antihistamine-decongestant combinations are the first-line treatment for upper airway cough syndrome (UACS), with intranasal corticosteroids recommended for cases with prominent upper airway symptoms. 1, 2

Understanding UACS

Upper airway cough syndrome, previously known as postnasal drip syndrome, is one of the most common causes of chronic cough. It's characterized by:

• Nasal stuffiness
• Sensation of secretions draining into the posterior pharynx
• Cough that may be accompanied by sinusitis 1

Treatment Algorithm

First-Line Therapy:

1. First-generation antihistamine-decongestant (A/D) combinations:

   • Examples: dexbrompheniramine maleate (6 mg twice daily) plus sustained-release pseudoephedrine sulfate (120 mg twice daily) 1
   • Duration: Minimum 3 weeks for optimal effect
   • Mechanism: Works primarily through anticholinergic properties rather than antihistamine effect 1

2. Intranasal corticosteroids:

   • Recommended for patients with prominent upper airway symptoms 1, 2
   • Duration: 1 month trial initially; may continue for 3 months if effective 1
   • Examples: fluticasone propionate 2

3. Saline nasal irrigation:

   • Adjunctive therapy that improves mucous clearance and enhances ciliary activity 2

Treatment Based on Specific Causes:

For UACS due to allergic rhinitis:

• Nasal corticosteroids
• Non-sedating antihistamines
• Nasal cromolyn
• Oral leukotriene inhibitors 1, 2

For UACS due to sinusitis:

• Antibiotics effective against H. influenzae, mouth anaerobes, and S. pneumoniae for at least 3 weeks
• First-generation A/D combinations for at least 3 weeks
• Nasal decongestant for 5 days maximum 1

For UACS due to non-allergic causes:

• First-generation antihistamines (preferred over newer generations due to anticholinergic effect) 1
• Ipratropium bromide nasal spray for rhinorrhea-predominant symptoms 2

Important Clinical Considerations

Diagnostic Approach

• UACS is a clinical diagnosis with no pathognomonic findings 1, 3
• Response to treatment is both diagnostic and therapeutic 2
• If no response to empiric A/D therapy, sinus imaging should be considered 1

Medication Administration Tips

• To minimize sedation from first-generation antihistamines, consider starting with once-daily dosing at bedtime before advancing to twice-daily 1
• Limit topical decongestants to 5-7 days to prevent rhinitis medicamentosa 2

Monitoring for Side Effects

• Common side effects of A/D combinations include:
  • Dry mouth and transient dizziness
  • Sedation (antihistamine component)
  • Insomnia, urinary retention, jitteriness, tachycardia, hypertension (decongestant component) 1
• Use with caution in patients with glaucoma, prostatic hypertrophy, or hypertension 1

Treatment Duration

• Improvement typically occurs within days to 2 weeks of starting therapy 1
• If cough persists despite 4 weeks of appropriate treatment, further investigation is warranted 2

Special Populations

• First-generation A/D combinations should not be used in children under 6 years due to safety concerns 2
• Start with lower doses in elderly patients, considering anticholinergic burden 2

By following this evidence-based approach to UACS treatment, clinicians can effectively manage this common cause of chronic cough while minimizing potential adverse effects.