Treatment Recommendations for Persistent Cough
For persistent cough, a stepwise approach is recommended, starting with dextromethorphan for symptomatic relief, followed by inhaled ipratropium for postinfectious cough, and considering inhaled corticosteroids or short-course oral prednisone for severe cases that don't respond to initial treatments. 1, 2
Initial Assessment and Classification
- Acute cough: <3 weeks (typically viral, self-limiting)
- Subacute cough: 3-8 weeks (often postinfectious)
- Chronic cough: >8 weeks (requires thorough evaluation)
Red Flags Requiring Immediate Medical Attention
- Coughing up blood
- Significant breathlessness
- Prolonged fever
- Pre-existing conditions with worsening cough
- Cough persisting >8 weeks despite treatment 2
Treatment Algorithm for Persistent Cough
Step 1: Supportive Care and OTC Options
Dextromethorphan: 30mg every 6-8 hours (not exceeding 120mg/24 hours) for non-productive cough 1, 3
- Most effective OTC cough suppressant
- Available in extended-release formulations for 12-hour relief
- Caution: Contains sulfites that may cause allergic reactions
Guaifenesin: For productive cough with thick mucus 4
- Helps loosen phlegm and thin bronchial secretions
- Makes coughs more productive
Home remedies: Honey and lemon, staying hydrated 2
Step 2: For Postinfectious Cough (3-8 weeks)
Inhaled ipratropium bromide: First-line pharmacologic treatment 2
- Shown to attenuate postinfectious cough in controlled trials
- Level of evidence: fair; net benefit: intermediate; grade: B
Antibiotics: Not recommended for postinfectious cough 2
- No evidence of benefit as bacterial infection is not the cause
- Level of evidence: expert opinion; net benefit: none; grade: I
Step 3: For Persistent Cough Despite Initial Treatment
Inhaled corticosteroids: Consider when cough affects quality of life and persists despite ipratropium 2
- Particularly effective for eosinophilic bronchitis
- Not recommended if tests for bronchial hyperresponsiveness and eosinophilia are negative
Short-course oral prednisone: For severe paroxysms of postinfectious cough 2
- 30-40mg daily for a short, finite period
- Taper over 2-3 weeks
- Only after ruling out other common causes (UACS, asthma, GERD)
Step 4: For Refractory Unexplained Chronic Cough
Gabapentin: Consider therapeutic trial 2
- Starting at 300mg once daily
- Gradually increase to maximum tolerable dose of 1,800mg daily in two divided doses
- Discuss side effects and reassess risk-benefit at 6 months
Speech pathology therapy: Multimodality approach 2
- Grade 2C recommendation for unexplained chronic cough
Proton pump inhibitors: Not recommended for unexplained chronic cough with negative workup for acid reflux 2
Special Considerations
Cough Due to Lung Tumors
- Surgical removal for early-stage NSCLC (stages I and II) 2
- External beam radiation and/or chemotherapy for advanced NSCLC 2
- Endobronchial treatment methods may provide relief in 51-90% of cases 2
- Central acting narcotic antitussives often required as adjunctive therapy 2
Unexplained Chronic Cough
- Consider referral to specialist cough clinic if cough persists >8 weeks despite appropriate treatment 2
- Protocol-based assessment including testing for bronchial hyperresponsiveness and eosinophilic bronchitis 2
Common Pitfalls to Avoid
Inappropriate antibiotic use: Antibiotics have no role in postinfectious cough and most acute coughs 2
Overlooking underlying causes: Always consider UACS, asthma, GERD, eosinophilic bronchitis, and medication side effects (especially ACE inhibitors) 1
Inadequate duration of treatment trials: Allow sufficient time for treatments to work before moving to next step
Failure to recognize when cough requires specialist referral: Consider specialist evaluation if cough persists >8 weeks despite treatment 2
Overlooking the impact on quality of life: Persistent cough significantly affects sleep, social interactions, and daily activities 2, 5