What is the treatment approach for a dry cough?

Treatment Approach for Dry Cough

The treatment of dry cough should follow a systematic, sequential approach targeting the underlying cause, starting with first-generation antihistamine/decongestant combinations for upper airway cough syndrome, inhaled corticosteroids for asthma or nonasthmatic eosinophilic bronchitis, and proton pump inhibitors for gastroesophageal reflux disease. 1

Initial Assessment

• Determine if the cough is acute (<3 weeks), subacute (3-8 weeks), or chronic (>8 weeks) to guide management approach 2
• Rule out serious conditions like pneumonia or pulmonary embolism that may present with cough 2
• Check if the patient is taking an ACE inhibitor, which can cause persistent dry cough - discontinue if present 1
• Advise smoking cessation for smokers, as this can resolve cough symptoms within 4 weeks 1, 3
• Obtain a chest radiograph to rule out significant pathology 1, 3

Treatment Algorithm Based on Common Causes

1. Upper Airway Cough Syndrome (UACS)

• Begin with a first-generation antihistamine/decongestant combination (e.g., chlorpheniramine plus pseudoephedrine) 1
• Expect improvement within 1-2 weeks, though complete resolution may take several weeks 1, 4
• Note that newer generation non-sedating antihistamines are ineffective for cough and should not be used 2

2. Asthma and Nonasthmatic Eosinophilic Bronchitis (NAEB)

• For suspected asthma, initiate treatment with inhaled corticosteroids (ICS) combined with long-acting β-agonists (LABA) 3
• For NAEB, first-line treatment is inhaled corticosteroids 2, 3
• If spirometry doesn't show reversible airflow obstruction, consider bronchoprovocation challenge to confirm asthma 1, 3
• Consider induced sputum testing for eosinophils or an empiric trial of corticosteroids for suspected NAEB 1, 3

3. Gastroesophageal Reflux Disease (GERD)

• Initiate empiric treatment with proton pump inhibitors if cough persists after addressing UACS and asthma 1, 3
• Add prokinetic therapy (e.g., metoclopramide) if there is little or no response to PPI therapy 1
• Implement antireflux diet and lifestyle modifications 1
• Response time is variable - some patients respond within 2 weeks while others may take several months 1, 5

Symptomatic Relief for Persistent Dry Cough

• For symptomatic relief when cough interferes with daily activities or sleep:
  • Codeine or dextromethorphan-containing antitussives can provide effective symptomatic relief 1, 4
  • First-generation antihistamines like chlorpheniramine may be beneficial, particularly when sedation is valuable for nighttime cough 4, 6
  • Consider low-dose morphine for idiopathic chronic cough that is refractory to other treatments 1, 5
  • Honey may be considered for cough suppression in patients over 1 year of age 2

Special Considerations

• For pediatric patients, use pediatric-specific cough management protocols 1
• In patients with lung cancer, consider endobronchial brachytherapy for cough due to localized endobronchial disease when surgery, chemotherapy, or external beam radiation are not indicated 1
• For patients with idiopathic chronic cough (no identifiable cause despite thorough evaluation):
  • Consider non-specific antitussive therapy such as dextromethorphan 1, 5
  • Consider nebulized local anesthetics (lidocaine, mepivicaine) in refractory cases 1, 6
  • Low-dose morphine has shown benefit in some cases 1, 5

Common Pitfalls to Avoid

• Do not rely solely on cough characteristics for diagnosis, as they have limited diagnostic value 1, 2
• Avoid treating only one potential cause, as multiple factors often contribute to chronic cough 1, 2
• Do not use expectorants like guaifenesin for dry cough - these are indicated for productive coughs to help loosen phlegm 7, 8
• Do not forget to consider uncommon causes when cough persists despite appropriate evaluation and treatment 1, 2
• Consider referral to a cough specialist if cough persists despite sequential trials of therapy for common causes 1, 3