What is the recommended treatment for upper airway cough syndrome?

Treatment for Upper Airway Cough Syndrome

First-generation antihistamine/decongestant combinations are the most effective first-line treatment for upper airway cough syndrome (UACS), with older-generation antihistamines being superior to newer non-sedating antihistamines due to their anticholinergic properties. 1, 2

Treatment Algorithm Based on Underlying Cause

First-Line Empiric Therapy

• For patients with chronic cough without an apparent specific etiology, empiric therapy with a first-generation antihistamine/decongestant (A/D) preparation should be prescribed before extensive diagnostic workup 1
• Specific effective combinations include:
  • Dexbrompheniramine maleate (6 mg twice daily) plus sustained-release pseudoephedrine sulfate (120 mg twice daily) 1
  • Azatadine maleate (1 mg twice daily) plus sustained-release pseudoephedrine sulfate (120 mg twice daily) 1

Treatment Based on Specific Causes

For Allergic Rhinitis-Related UACS:

• Nasal corticosteroids, antihistamines, and/or cromolyn are the initial drug choices 1, 2
• Oral leukotriene inhibitors may also be effective 1, 2
• Non-sedating antihistamines may be more effective for allergic rhinitis than for non-allergic causes 1, 2

For Post-Viral Upper Respiratory Infection:

• First-generation A/D combinations have proven efficacy in both acute and chronic cough 1
• Newer generation antihistamines (with or without pseudoephedrine) are ineffective and should not be used 1, 3
• Naproxen can be administered alongside A/D preparations to help decrease cough 1

For Sinusitis-Related UACS:

• For chronic sinusitis, the following regimen has shown efficacy: 1
  • Minimum 3 weeks of antibiotics effective against H. influenzae, mouth anaerobes, and S. pneumoniae
  • Minimum 3 weeks of oral treatment with older-generation A/D twice daily
  • 5 days of treatment with a nasal decongestant twice daily
  • Continue intranasal corticosteroids for 3 months after cough resolution

For Rhinitis Due to Physical or Chemical Irritants:

• Avoidance of exposure, improved ventilation, filters, and in rare circumstances, personal protective devices 1

Diagnostic Approach

• If a patient does not respond to empiric A/D therapy with a first-generation antihistamine, sinus imaging should be performed 1
• UACS is a clinical diagnosis determined by considering symptoms, physical examination findings, radiographic findings, and response to therapy 1, 4
• UACS can present as "silent" with no obvious symptoms yet respond to treatment 2, 5

Important Clinical Considerations

• Most patients will see improvement in cough within days to 2 weeks of initiating therapy 1, 2
• To minimize sedation from first-generation antihistamines, consider starting with once-daily dosing at bedtime for a few days before increasing to twice-daily therapy 1, 2
• Ipratropium bromide nasal spray is an alternative for patients who don't respond to A/D combinations or have contraindications 1

Common Side Effects and Monitoring

• Common side effects of first-generation antihistamines include dry mouth and transient dizziness 1, 2
• More serious side effects to monitor for include: 1, 2
  • Insomnia
  • Urinary retention (primarily in older men)
  • Jitteriness
  • Tachycardia or palpitations
  • Worsening of hypertension
  • Increased intraocular pressures in glaucoma patients

Common Pitfalls and Caveats

• Newer-generation antihistamines are ineffective for reducing cough in UACS and should not be used 1, 3
• For rhinitis medicamentosa, the key to therapy is stopping or weaning off the offending agent 1
• UACS, asthma, and gastroesophageal reflux make up 90% of causes of chronic cough, so consider these diagnoses in all patients with chronic cough 4
• Chronic sinusitis may cause a productive cough, but it may also be clinically silent with no typical findings of acute sinusitis 1
• In acute upper respiratory tract infection, bacterial sinusitis should not be diagnosed during the first week of symptoms 1