What is the treatment for chronic cough?

Treatment for Chronic Cough

The treatment for chronic cough should follow a sequential approach targeting the three most common causes: upper airway cough syndrome (UACS), asthma, and gastroesophageal reflux disease (GERD), starting with empiric therapy for UACS using first-generation antihistamine-decongestant combinations. 1

Initial Evaluation

• Chest radiography: Essential first step to rule out serious pathology
• Medication review: Check for ACE inhibitors or sitagliptin which can cause chronic cough
• Smoking status: Smoking cessation should always be encouraged
• Pulmonary function testing: To evaluate for asthma or COPD

Treatment Algorithm

Step 1: Upper Airway Cough Syndrome (UACS)

• Begin with first-generation antihistamine-decongestant (A/D) therapy
• Assess response within 1-3 weeks
• If complete resolution: Continue A/D therapy
• If partial resolution: Continue A/D and proceed to Step 2

Step 2: Asthma

• For patients with suspected asthma: Trial of inhaled corticosteroids with or without bronchodilators
• For patients with chronic bronchitis:
  • LABA/ICS combination (e.g., salmeterol/fluticasone) 2
  • LAMA (e.g., ipratropium bromide) for first-line bronchodilator therapy 2
  • Consider LABA/LAMA combinations for inadequate response to monotherapy 2

Step 3: GERD

If cough persists after addressing UACS and asthma, treat for GERD:

• Dietary and lifestyle modifications:
  • Limit fat intake to <45g/24h
  • Avoid coffee, tea, soda, chocolate, mints, citrus products, tomatoes, alcohol
  • No smoking
  • Limit vigorous exercise that increases intra-abdominal pressure 1
• Acid suppression therapy:
  • Start with proton pump inhibitors (PPIs)
  • If no response within 1-3 months, add prokinetic therapy 1
• Note: PPI therapy should not be used if workup for acid reflux is negative 1

Step 4: Refractory Chronic Cough

For persistent cough despite optimal treatment of common causes:

• Neuromodulators:

  • Gabapentin (first-line) after discussing potential side effects and risk-benefit profile 1
  • Low-dose slow-release morphine (5-10 mg twice daily) for intractable cases 2
  • Codeine or dextromethorphan for short-term symptomatic relief 2

• Non-pharmacological approaches:

  • Speech and language therapy 3
  • Pulmonary rehabilitation for patients with chronic bronchitis 2

Special Considerations

Chronic Bronchitis

• Defined as cough with sputum production for at least 3 months per year during 2 consecutive years 1
• Pharmacological management:
  • LAMA as first-line therapy, evaluate response after 4-6 weeks 2
  • Add LABA if inadequate response 2
  • Inhaled corticosteroids for severe lung function impairment or frequent exacerbations 2

Multifactorial Causes

• Many patients have two or all three common causes (UACS, asthma, GERD)
• Cough will not resolve until all contributing factors are effectively treated 1

Monitoring

• Regular assessment of symptoms
• Evaluate treatment adherence and inhaler technique at each visit
• If empiric treatment fails for GERD, objective investigation is recommended as therapy may not have been intensive enough 1

Pitfalls to Avoid

1. Overlooking multifactorial causes: Chronic cough is often caused by multiple conditions simultaneously
2. Premature discontinuation of therapy: Allow adequate trial periods (1-3 months for GERD therapy)
3. Attributing cough to interstitial lung disease without evaluating for common causes
4. Inadequate intensity of GERD therapy: May require combination of dietary changes, acid suppression, and prokinetic therapy
5. Failing to consider antireflux surgery for GERD-related cough that fails maximal medical therapy 1

By following this systematic approach to chronic cough, most cases can be effectively diagnosed and treated, improving patient quality of life and reducing morbidity.