When should bronchitis be treated with antibiotics?

When to Treat Bronchitis with Antibiotics

Antibiotics should NOT be prescribed for acute bronchitis in otherwise healthy adults, as the benefit has not been confirmed in clinical trials versus placebo. 1

Classification of Bronchitis and Antibiotic Indications

Acute Bronchitis

• Acute bronchitis is usually caused by viruses and does not require antibiotic therapy in otherwise healthy adults 1, 2
• Consider antibiotics only if fever (>38°C) persists for more than 3 days 1, 3
• Purulent sputum or change in sputum color (green or yellow) does not necessarily indicate bacterial infection 1

Chronic Bronchitis

Antibiotic indications depend on the stage of chronic bronchitis:

Simple Chronic Bronchitis

• Characterized by chronic cough and expectoration without dyspnea, FEV1>80% 3
• Immediate antibiotic therapy is not recommended, even if fever is present 3, 4
• Antibiotics only recommended if fever (>38°C) persists for more than 3 days 3, 1

Obstructive Chronic Bronchitis

• Characterized by exertional dyspnea and/or FEV1 between 35% and 80% 3
• Immediate antibiotic therapy is only recommended if at least two of the three Anthonisen criteria are present:
  • Increased sputum volume
  • Increased sputum purulence
  • Increased dyspnea 3, 4, 1
• During reassessment, antibiotics recommended if fever (>38°C) persists for more than 3 days 3

Chronic Obstructive Bronchitis with Chronic Respiratory Insufficiency

• Characterized by dyspnea at rest and/or FEV1 <35% and hypoxemia at rest 3
• Immediate antibiotic therapy is recommended during exacerbations 3, 4, 1

Antibiotic Selection

First-Line Options

For infrequent exacerbations in patients with FEV1 ≥35%:

• Amoxicillin (reference compound) 3, 1
• First-generation cephalosporins as an alternative 3, 1
• For penicillin allergy: macrolides, pristinamycin, or doxycycline 3, 4, 1

Second-Line Options

For frequent exacerbations or failure of first-line therapy:

• Amoxicillin-clavulanate (reference second-line therapy) 1, 5
• Second or third-generation oral cephalosporins 1
• Fluoroquinolones active against pneumococci (levofloxacin, moxifloxacin) 1, 6, 5

Target Pathogens

Antibiotic therapy should be active against:

• Streptococcus pneumoniae 3, 1
• Haemophilus influenzae 3, 1
• Moraxella catarrhalis (formerly Branhamella catarrhalis) 3, 1

Duration of Treatment

• Standard duration of antibiotic treatment is 7-10 days 3, 4
• For acute exacerbation of chronic bronchitis, azithromycin has shown efficacy with a 3-day regimen 7

Common Pitfalls to Avoid

• Prescribing antibiotics for acute bronchitis in healthy adults without clear indications 1, 8
• Assuming purulent sputum indicates bacterial infection 1
• Failing to distinguish between acute bronchitis and pneumonia 1
• Using antibiotics with inadequate coverage (cotrimoxazole has inconsistent activity against pneumococci and a poor benefit/risk ratio) 3, 1
• Overlooking viral causes, which account for approximately one-third of acute exacerbations 9
• Not considering the risk of antibiotic resistance when prescribing antibiotics for mild cases 8, 10

Clinical Monitoring

• Fever should resolve within 2-3 days after starting antibiotic treatment 4, 1
• Clinical reassessment should be performed after 5-7 days of treatment 4
• Persistent fever >38°C after 3 days suggests bacterial infection or pneumonia 3, 4