What antibiotics are recommended for treating bronchitis?

Antibiotic Recommendations for Bronchitis

Antibiotics should NOT be routinely prescribed for acute bronchitis in otherwise healthy adults, as this condition is predominantly viral (89-95% of cases) and antibiotics provide minimal clinical benefit while exposing patients to unnecessary adverse effects and contributing to antibiotic resistance. 1, 2

Acute Bronchitis in Immunocompetent Adults

Evidence Against Routine Antibiotic Use

• Routine antibiotic treatment is not recommended regardless of cough duration, as multiple systematic reviews demonstrate antibiotics reduce cough duration by only approximately 0.5 days while increasing adverse events. 1, 2, 3
• The WHO Essential Medicines guidelines explicitly state antibiotics should not be recommended for acute bronchitis in otherwise healthy people. 2
• Meta-analyses show no significant difference in clinical improvement between antibiotic and placebo groups (RR 1.07; 95% CI 0.99-1.15), while adverse events occur more frequently with antibiotics (16% vs. 11%). 2
• The FDA removed uncomplicated acute bronchitis as an indication for antimicrobial therapy in 1998. 1

When to Consider Antibiotics in Acute Bronchitis

• If acute bronchitis worsens or fails to improve, reassess the patient and consider antibiotic therapy only if a complicating bacterial infection (such as pneumonia) is thought likely. 1
• Rule out pneumonia in patients with tachycardia (>100 beats/min), tachypnea (>24 breaths/min), fever (>38°C), or abnormal chest examination findings. 2
• The presence of purulent or green/yellow sputum does NOT indicate bacterial infection—this is due to inflammatory cells and sloughed epithelial cells, not bacteria. 2

Exception: Pertussis (Whooping Cough)

• For confirmed or suspected pertussis, prescribe a macrolide antibiotic such as erythromycin or azithromycin. 2, 4
• Early treatment within the first few weeks helps diminish coughing paroxysms and prevent disease spread. 2
• Isolate patients for 5 days from the start of treatment. 2

Chronic Bronchitis Exacerbations

The approach differs significantly for patients with underlying chronic bronchitis or COPD:

Simple Chronic Bronchitis (FEV1 >80%, no dyspnea)

• Immediate antibiotic therapy is NOT recommended, even if fever is present. 1
• Reassess after 2-3 days: prescribe antibiotics only if fever (>38°C) persists for more than 3 days. 1

Chronic Obstructive Bronchitis (FEV1 35-80%, exertional dyspnea)

• Immediate antibiotic therapy is recommended only if at least 2 of 3 Anthonisen criteria are present: increased dyspnea, increased sputum volume, and increased sputum purulence. 1
• On reassessment, prescribe antibiotics if fever (>38°C) persists for more than 3 days OR if 2 of 3 Anthonisen criteria are present without fever. 1

Severe Chronic Obstructive Bronchitis with Respiratory Insufficiency (FEV1 <35%, dyspnea at rest, hypoxemia)

• Immediate antibiotic therapy is recommended. 1

Antibiotic Selection for Chronic Bronchitis Exacerbations

Target pathogens are S. pneumoniae, H. influenzae, and M. catarrhalis. 1

First-Line Antibiotics

Use for infrequent exacerbations (≤3 per year) in patients with FEV1 ≥35%:

• Amoxicillin remains the reference first-line antibiotic. 1
• First-generation cephalosporins are an alternative. 1
• Macrolides (erythromycin, azithromycin), pristinamycin, or doxycycline are alternatives, particularly for beta-lactam allergy. 1, 4
• Avoid cotrimoxazole due to inconsistent pneumococcal activity and poor benefit/risk ratio. 1

Second-Line Antibiotics

Use for frequent exacerbations (≥4 per year), baseline FEV1 <35%, or first-line antibiotic failure:

• Amoxicillin-clavulanate is the reference second-line antibiotic. 1
• Second-generation cephalosporins (cefuroxime-axetil) or third-generation cephalosporins (cefpodoxime-proxetil, cefotiam-hexetil) are alternatives. 1
• Respiratory fluoroquinolones active against pneumococci (levofloxacin, moxifloxacin) are appropriate alternatives, particularly for patients with risk factors including severe obstruction, age >65 years, or recurrent exacerbations. 1, 5, 6
• Avoid fluoroquinolones inactive against pneumococci (ofloxacin, ciprofloxacin) and cefixime. 1
• Reserve ciprofloxacin for suspected Pseudomonas aeruginosa infections. 1

Patient Communication Strategies

• Refer to acute bronchitis as a "chest cold" rather than "bronchitis" to reduce antibiotic expectations. 2
• Inform patients that cough typically lasts 10-14 days after the office visit, sometimes up to 2-3 weeks. 2, 7
• Explain that patient satisfaction depends more on physician-patient communication than whether an antibiotic is prescribed. 2
• Discuss risks of unnecessary antibiotic use, including side effects (nausea, vomiting, diarrhea) and contribution to antibiotic resistance. 2

Important Caveats

• These recommendations for acute bronchitis do NOT apply to elderly patients or those with comorbid conditions such as COPD, congestive heart failure, or immunosuppression. 2
• Always reassess patients who fail to improve or worsen, as this may indicate pneumonia or other complications requiring different management. 1
• Consider antiviral medications for influenza-related bronchitis if within 48 hours of symptom onset. 2