When are antibiotics indicated for a cough?

When to Use Antibiotics for Cough

Antibiotics are rarely indicated for acute cough and should only be prescribed for specific conditions including confirmed bacterial pneumonia, pertussis (whooping cough), bacterial sinusitis, and exacerbations of bronchiectasis or severe chronic bronchitis in patients with severe airflow obstruction. 1

Conditions That DO Warrant Antibiotic Therapy

1. Suspected or Confirmed Pneumonia

• Antibiotics should be used when pneumonia is suspected in settings where imaging cannot be obtained 1
• Clinical features suggesting pneumonia include:
  • Fever ≥38°C
  • Dyspnea
  • Pleural pain
  • Absence of runny nose
  • Tachypnea
  • New and localizing chest examination findings 2
• Radiographic confirmation is preferred when available

2. Pertussis (Whooping Cough)

• Suspect pertussis when cough persists >2 weeks with:
  • Paroxysmal coughing
  • Post-tussive vomiting
  • Inspiratory whooping sound 1
• Macrolide antibiotics (erythromycin, azithromycin, or clarithromycin) should be given to:
  • Confirmed cases
  • Probable cases with epidemiologic linkage to a confirmed case 1
• Early treatment (within first few weeks) will:
  • Diminish coughing paroxysms
  • Prevent disease transmission
  • Patient should be isolated for 5 days from start of treatment 1

3. Bacterial Sinusitis

• Antibiotics are indicated for bacterial sinusitis causing upper airway cough syndrome 1
• Consider this diagnosis if cough worsens (biphasic course) or does not steadily improve after the first week of illness 1

4. Specific Types of Bronchiolitis

• Bacterial bronchiolitis: Prolonged antibiotic therapy improves cough 1
• Diffuse panbronchiolitis (DPB): Prolonged treatment (≥2-6 months) with macrolides is indicated 1

5. Severe Exacerbations of Chronic Lung Disease

• Exacerbations of bronchiectasis
• Severe chronic bronchitis in current or previous smokers with severe airflow obstruction 1

Conditions That DO NOT Warrant Antibiotic Therapy

1. Acute Bronchitis

• Routine treatment with antibiotics is not justified 1
• Acute bronchitis is primarily viral (>90% of cases) 3, 4
• Antibiotics provide minimal benefit (reducing cough by only about half a day) 3
• Risks include allergic reactions, nausea, vomiting, and C. difficile infection 3

2. Common Cold

• Antibiotics are not indicated for acute cough from the common cold 1
• First-generation antihistamine/decongestant or naproxen may be more appropriate 1

3. Postinfectious Cough

• When cough persists 3-8 weeks following acute respiratory infection
• Antibiotics have no role as the cause is not bacterial infection 1
• Consider inhaled ipratropium or inhaled corticosteroids instead 1

4. Asthma or Environmental Irritant-Related Cough

• Antibiotics are not indicated 1

Important Clinical Pearls

• The presence of colored (green/purulent) sputum does not reliably differentiate between bacterial and viral infections 4

• Cough from uncomplicated viral infections is typically worst in the first few days and gradually improves over 1-2 weeks 1

• When antibiotics are necessary, select the appropriate agent based on the suspected pathogen:

  • For pertussis: Macrolides (erythromycin, azithromycin, clarithromycin) 5, 6
  • For pneumonia: Follow local guidelines, often azithromycin or amoxicillin-clavulanate 2

• Patient education about the natural course of viral respiratory infections and the limited role of antibiotics is essential to reduce inappropriate antibiotic use 4

• For patients expecting antibiotics, take time to explain the decision not to use them and the potential harm of unnecessary antibiotics to both the individual and community 1

By following these evidence-based guidelines, clinicians can ensure appropriate antibiotic stewardship while effectively managing patients with cough.