What is the treatment for a patient with chronic cough?

Treatment of Chronic Cough

For patients with chronic cough, systematically treat the three most common causes—upper airway cough syndrome (UACS), asthma, and gastroesophageal reflux disease (GERD)—using sequential empiric therapy, as these account for over 80% of cases and frequently coexist. 1, 2

Initial Actions Before Starting Treatment

• Discontinue ACE inhibitors immediately if the patient is taking one, as this resolves cough in days to 2 weeks (median 26 days) 2, 3
• Counsel smoking cessation aggressively, as 90% of patients with chronic bronchitis will have cough resolution after quitting 2
• Obtain chest radiograph and spirometry to rule out serious pathology and assess for obstructive or restrictive patterns 3, 4

Sequential Treatment Algorithm

Step 1: Treat Upper Airway Cough Syndrome (UACS) First

• Start a first-generation antihistamine/decongestant combination (such as brompheniramine with sustained-release pseudoephedrine) as first-line empiric therapy 2, 3
• Newer non-sedating antihistamines are ineffective for UACS—first-generation agents are required 2
• Expect response within 1-2 weeks, though complete resolution may take several weeks 2, 3
• Add saline nasal irrigation and humidification as supportive measures 5
• Consider intranasal corticosteroids if nasal symptoms persist 5

Step 2: Add Asthma Treatment After 2-4 Weeks If Cough Persists

• Initiate inhaled corticosteroids (ICS) combined with long-acting β-agonists (LABA), such as fluticasone/salmeterol twice daily 2, 3
• ICS alone is recommended for non-asthmatic eosinophilic bronchitis (NAEB) when airway eosinophilia is confirmed 1
• Monitor for response within 2-4 weeks 2, 3
• Do not stop UACS treatment—continue it as multiple conditions often contribute simultaneously 2

Step 3: Add GERD Treatment If Inadequate Response After 1-2 Months

• Start proton pump inhibitor (PPI) therapy with dietary modifications 1, 2
• Dietary restrictions include: no more than 45g fat per 24 hours, avoid coffee, tea, soda, chocolate, mints, citrus (including tomatoes), and alcohol 1
• Add prokinetic therapy (such as metoclopramide) if PPI alone is ineffective after 1-3 months 1
• Assess response over 1-3 months, as GERD-related cough takes longer to resolve than UACS or asthma 1, 2
• Continue all previous treatments during this phase 2, 3

Treatment for Specific Etiologies

Non-Asthmatic Eosinophilic Bronchitis (NAEB)

• First-line treatment is inhaled corticosteroids when airway eosinophilia is confirmed by sputum induction or bronchial wash 1
• Identify and avoid causal allergens or occupational sensitizers when possible 1
• Use oral corticosteroids if symptoms persist despite high-dose ICS 1

Chronic Bronchitis

• Short-term central cough suppressants (codeine or dextromethorphan) are recommended for symptomatic relief 1
• For acute exacerbations, give a 10-15 day course of systemic corticosteroids (IV for hospitalized patients, oral for ambulatory patients) 1

Bronchiectasis

• Use bronchodilators when airflow obstruction or bronchial hyperreactivity is present 1
• Consider prolonged antibiotic therapy for idiopathic bronchiectasis to reduce sputum volume and purulence 1

Refractory or Unexplained Chronic Cough

When cough persists despite optimal treatment of UACS, asthma, and GERD:

• Gabapentin is recommended as a neuromodulatory agent, starting at doses used in the Ryan trial, with reassessment of risk-benefit at 6 months 1
• Consider speech pathology interventions for cough hypersensitivity syndrome 1, 6
• Morphine may be considered only when all other therapeutic options have failed, with close follow-up at 1 week then monthly 1
• Amitriptyline showed positive effects but verification of results was not possible, limiting its recommendation 1

For Unexplained Chronic Cough with Negative Testing

• Do not prescribe inhaled corticosteroids if bronchial hyperresponsiveness testing and eosinophilia markers (sputum eosinophils, exhaled nitric oxide) are negative 1

Critical Pitfalls to Avoid

• Never assume a single cause—use sequential and additive therapy as multiple conditions frequently coexist 2, 3
• Do not use newer non-sedating antihistamines for UACS—they are ineffective 2
• Do not stop partially effective treatments when adding new therapies—maintain all treatments that provide benefit 2
• Do not assume GERD is ruled out if empiric treatment fails—the therapy may not have been intensive enough, and objective investigation is then warranted 1
• Avoid codeine and dextromethorphan in first trimester pregnancy except with extreme caution 5

When to Refer or Investigate Further

• Red flags requiring immediate investigation: fever, night sweats, weight loss, hemoptysis, history of tuberculosis or cancer, abnormal chest radiograph 5, 6
• Consider referral to pulmonology or otolaryngology if cough persists despite 4-6 weeks of sequential empiric therapy for all three common causes 2, 7
• High-resolution CT scan is indicated for suspected bronchiectasis without characteristic chest radiograph findings 1

Expected Timeline for Overall Resolution

• UACS: 1-2 weeks for initial improvement 2, 3
• Asthma: 2-4 weeks 2, 3
• GERD: 1-3 months 1, 2
• Overall resolution may require maintaining all partially effective treatments for several months 2