What oral prednisone dose and duration should be used for an adult with upper airway cough syndrome?

Prednisone Dosing for Upper Airway Cough Syndrome (UACS)

For postinfectious cough or severe UACS unresponsive to other treatments, prescribe prednisone 30-40 mg orally once daily for 5 days without tapering. 1

Primary Treatment Approach for UACS

Upper airway cough syndrome (previously called postnasal drip syndrome) should first be treated with topical nasal corticosteroids for 1 month before considering systemic steroids. 1 This is the guideline-recommended first-line approach for UACS with prominent upper airway symptoms. 1

When to Use Systemic Prednisone

Oral prednisone is reserved for specific scenarios in UACS:

Postinfectious Cough (Most Common Indication)

• For severe paroxysms of postinfectious cough that adversely affect quality of life and persist despite inhaled ipratropium, prescribe prednisone 30-40 mg daily for a short, finite period after ruling out other common causes like asthma or GERD. 1
• This recommendation applies when cough has persisted 3-8 weeks following an acute respiratory infection. 1
• The optimal duration is 5 days, consistent with evidence-based protocols for respiratory conditions. 2, 3

Cough Variant Asthma (If UACS Overlaps with Asthma)

• If diagnostic uncertainty exists between UACS and cough variant asthma, a diagnostic-therapeutic trial of prednisone 30 mg daily for 1-2 weeks can establish the diagnosis. 4, 5
• Cough should improve within 3 days to 2 weeks if asthma-related. 5
• Follow with inhaled corticosteroids for long-term control rather than continuing oral steroids. 4

Critical Treatment Algorithm

Step 1: Confirm UACS diagnosis by presence of nasal stuffiness, sinusitis, or sensation of posterior pharyngeal drainage. 1

Step 2: Initiate topical nasal corticosteroid (e.g., fluticasone, mometasone) for 1 month as first-line therapy. 1

Step 3: If cough persists and is severe/debilitating after 1 month of nasal steroids:

• Rule out asthma (consider methacholine challenge or trial of bronchodilators). 1
• Rule out GERD (consider PPI trial 20-40 mg twice daily for 8 weeks). 1

Step 4: If postinfectious cough is suspected (recent URI within 3-8 weeks) and other causes excluded:

• Prescribe prednisone 30-40 mg orally once daily for 5 days. 1, 2
• No tapering required for courses ≤14 days. 2
• Stop abruptly after day 5. 2

Important Caveats and Pitfalls

Do NOT Use Prednisone as First-Line for UACS

• Topical nasal steroids are the evidence-based first approach for UACS. 1
• Systemic steroids should only be considered after failure of topical therapy and exclusion of other causes. 1

Avoid Prolonged Courses

• Never extend prednisone beyond 5-7 days for postinfectious cough, as longer courses increase adverse effects (hyperglycemia, weight gain, insomnia) without additional benefit. 2, 3
• Courses up to 14 days can be stopped abruptly without tapering. 2

Consider Alternative Diagnoses

• UACS symptoms and clinical findings are not reliable discriminators for establishing UACS as the cause of cough. 1
• Many patients with observable postnasal secretions do not cough. 1
• Always consider asthma (especially cough variant asthma), GERD, and eosinophilic bronchitis as alternative or coexisting diagnoses. 1

Antihistamine Evidence is Conflicting

• First-generation sedating antihistamines recommended in U.S. guidelines are not available in the UK. 1
• There is conflicting evidence regarding efficacy of second-generation (non-sedating) antihistamines for chronic cough. 1

Monitoring and Follow-Up

• Assess response within 3-7 days of initiating prednisone. 5
• If no improvement after 1-2 weeks, reconsider the diagnosis. 1, 4
• Transition to inhaled corticosteroids if asthma component is identified. 4, 6
• Monitor for hyperglycemia, especially in diabetic patients (odds ratio 2.79 for hyperglycemia with short-term prednisone). 2