What antibiotics should be given to an adult patient with a history of recurrent nonproductive cough, who is now presenting with fever and has not responded to previous antibiotic treatments?

Antibiotic Selection for Adult with Recurrent Nonproductive Cough Now Presenting with Fever

For an adult with recurrent nonproductive cough who now presents with fever and has failed previous antibiotic treatments, you should NOT routinely prescribe antibiotics without first ruling out pneumonia and considering non-bacterial causes. 1

Critical Initial Assessment

Before prescribing any antibiotic, you must determine if pneumonia is present. 1

Clinical Criteria to Rule Out Pneumonia

For healthy immunocompetent adults younger than 70 years, pneumonia is unlikely if ALL of the following are absent: 1

• Tachycardia (heart rate >100 beats/min)
• Tachypnea (respiratory rate >24 breaths/min)
• Fever (oral temperature >38°C)
• Abnormal chest examination findings (rales, egophony, or tactile fremitus)

If all four criteria are absent, this is acute bronchitis, NOT pneumonia, and antibiotics are NOT indicated. 1

Management Algorithm Based on Clinical Findings

If NO Pneumonia (Acute Bronchitis or Postinfectious Cough)

Do NOT prescribe antibiotics. 1

• Antibiotics have no role in postinfectious cough or acute bronchitis, as the cause is not bacterial infection 1
• A systematic review of 15 randomized controlled trials found limited evidence to support antibiotics for acute bronchitis and a trend toward increased adverse events 1
• One study showed patients treated with macrolides had significantly more adverse events than those receiving placebo 1

Instead, consider: 1

• First-line: Inhaled ipratropium bromide (may attenuate cough) 1
• Second-line: Inhaled corticosteroids if cough persists despite ipratropium and adversely affects quality of life 1
• For severe paroxysms: Prednisone 30-40 mg daily for a short, finite period after ruling out upper airway cough syndrome, asthma, or gastroesophageal reflux disease 1
• Last resort: Central acting antitussives (codeine or dextromethorphan) when other measures fail 1

If Pneumonia IS Present

The choice of antibiotic depends on comorbidities and prior antibiotic exposure. 1, 2

For Previously Healthy Adults WITHOUT Comorbidities:

First-line: Amoxicillin 1 gram three times daily for 5-7 days 2

Alternatives: 2

• Doxycycline 100 mg twice daily for 5-7 days
• Macrolide (azithromycin or clarithromycin) ONLY if local pneumococcal macrolide resistance is documented <25%

For Adults WITH Comorbidities or Recent Antibiotic Failure:

This patient has failed previous antibiotics, which is a critical red flag. 1, 2

Combination therapy is mandatory: 2

• Amoxicillin-clavulanate 875/125 mg twice daily PLUS azithromycin 500 mg day 1, then 250 mg daily for 5-7 days 2, 3

Alternative: Respiratory fluoroquinolone monotherapy 2

• Levofloxacin 750 mg once daily for 5 days 2, 4
• Moxifloxacin 400 mg once daily for 5 days 2

Critical consideration: Since this patient failed previous antibiotics, you MUST select an agent from a different antibiotic class than recently used to reduce resistance risk 2

Special Diagnostic Considerations for Recurrent Cough with Fever

Consider Pertussis (Whooping Cough)

If cough has lasted ≥2 weeks with paroxysms, post-tussive vomiting, or inspiratory whooping sound, suspect Bordetella pertussis. 1

• Order nasopharyngeal aspirate or Dacron swab for culture (isolation is the only certain diagnosis) 1
• PCR is available but not recommended as there is no universally accepted, validated technique 1
• If confirmed early: Macrolide therapy (azithromycin, clarithromycin, or erythromycin) is appropriate 1

Red Flags Requiring Further Investigation

Failure of empirical therapy mandates reassessment. 1

The European Respiratory Society recommends the following investigations when antibiotics fail: 1

• Sputum microbiological examination (recommended)
• Blood white cell count and C-reactive protein (recommended)
• Blood cultures and serology (to be considered)
• Chest radiograph to rule out complications

Consider non-infectious causes: 5

• A 47-year-old with "non-resolving pneumonia" after three courses of antibiotics over 2 years was ultimately diagnosed with squamous cell carcinoma 5
• Bronchoscopy should be considered if fever and cough persist despite appropriate antibiotic therapy 5, 6

Common Pitfalls to Avoid

Never use macrolide monotherapy in patients with: 2

• Any comorbidities
• Recent antibiotic exposure (within 90 days)
• Areas with ≥25% pneumococcal macrolide resistance
• Requirement for hospitalization

Never prescribe antibiotics for acute bronchitis without pneumonia. 1 This contributes to antibiotic resistance and provides no clinical benefit while increasing adverse events.

Never assume fever + cough = bacterial infection requiring antibiotics. 1 Most cases are viral and self-limited.

Always reassess at 48 hours. 1 Patients should be told to return if fever does not resolve within 48 hours, as this suggests treatment failure or alternative diagnosis.