What is the recommended treatment for acute bronchitis and chronic bronchitis?

Treatment of Acute and Chronic Bronchitis

Acute Bronchitis – Do NOT Use Antibiotics

Antibiotics should not be prescribed for acute bronchitis in otherwise healthy adults because they reduce cough by only half a day while significantly increasing adverse effects and antimicrobial resistance. 1, 2

Diagnostic Approach

• Rule out pneumonia first by checking for heart rate >100 bpm, respiratory rate >24 breaths/min, oral temperature >38°C, or abnormal chest findings (focal consolidation, egophony, fremitus); if any are present, obtain chest radiography rather than treating as bronchitis 1, 2
• Respiratory viruses cause 89–95% of acute bronchitis cases, making antibiotics completely ineffective regardless of which agent you choose 2
• Purulent (green/yellow) sputum occurs in 89–95% of viral cases and does NOT indicate bacterial infection—it reflects inflammatory cells, not bacteria 1, 2
• Cough duration is not a marker of bacterial infection; viral bronchitis cough typically lasts 10–14 days and may persist up to 3 weeks 2

Symptomatic Management Only

• Explain to patients that cough will last 10–14 days (up to 3 weeks) and that antibiotics do not shorten the illness while exposing them to side effects (diarrhea, rash, yeast infections) and promoting resistance 2
• Codeine or dextromethorphan provide modest relief for bothersome dry cough, especially when it disturbs sleep 2
• Short-acting β₂-agonists (albuterol) should be used only when wheezing accompanies the cough 2
• Remove environmental irritants and use humidified air 2

The One Exception – Pertussis

• When pertussis is confirmed or strongly suspected (paroxysmal cough, post-tussive vomiting, inspiratory "whoop," cough >2 weeks), prescribe a macrolide (azithromycin or erythromycin) immediately and isolate the patient for 5 days from treatment start 1, 2
• Early macrolide therapy reduces cough paroxysms and limits transmission 2

Red-Flag Criteria for Re-evaluation

• Fever persisting >3 days suggests possible bacterial superinfection or pneumonia—reassess and consider chest radiography 2
• Cough lasting >3 weeks warrants evaluation for asthma, COPD, pertussis, or GERD 2
• Worsening symptoms rather than gradual improvement should prompt reconsideration of the diagnosis 2

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Chronic Bronchitis – Maintenance Therapy

First-Line Bronchodilator Therapy

• Ipratropium bromide (36 μg, two inhalations four times daily) is the preferred initial treatment for cough in stable chronic bronchitis, reducing cough frequency, severity, and sputum volume 1, 3
• Short-acting β₂-agonists (albuterol) improve pulmonary function, breathlessness, and exercise tolerance; add only when bronchospasm is documented or response to ipratropium is inadequate 1, 3
• For patients with FEV₁ <50% predicted or frequent exacerbations, escalate to a long-acting β₂-agonist plus inhaled corticosteroid 3, 4

Symptomatic Cough Suppressants (Short-Term Use Only)

• Codeine (≈30 mg orally three times daily) or dextromethorphan reduce cough counts by 40–60% in chronic bronchitis when cough severely impairs quality of life despite optimal bronchodilator therapy 3
• These are for short-term symptomatic relief only, not routine therapy 3

The Single Most Effective Intervention

• Smoking cessation is the most effective intervention—approximately 90% of patients experience cough resolution, typically within the first month after quitting, with benefits sustained long-term 1, 3, 4
• Eliminate all respiratory irritant exposures (passive smoke, occupational dusts, environmental pollutants) 3

What NOT to Use in Stable Chronic Bronchitis

• Do NOT use prophylactic antibiotics in stable patients—they offer no benefit and promote resistance 1, 3, 4
• Do NOT use expectorants (guaifenesin)—no proven benefit 3
• Do NOT use postural drainage or chest percussion—clinical benefits have not been demonstrated 1, 3
• Do NOT use long-term oral corticosteroids—no benefit with significant side effects 3, 4

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Acute Exacerbations of Chronic Bronchitis (AECB) – When Antibiotics ARE Indicated

Antibiotic Indications (Anthonisen Criteria)

Antibiotics are recommended for acute exacerbations when the patient has at least TWO of the three Anthonisen criteria: 1, 4, 5

1. Increased dyspnea
2. Increased sputum volume
3. Increased sputum purulence

AND at least ONE high-risk factor: 4, 5, 6

• Age ≥65 years
• FEV₁ <50% predicted
• ≥4 exacerbations in 12 months
• Cardiac failure, insulin-dependent diabetes, chronic renal insufficiency, chronic neurologic disease, immunosuppression, or malignancy

Antibiotic Selection Algorithm

For moderate-severity AECB (first-line options): 4, 5

• Doxycycline 100 mg twice daily for 7–10 days (preferred)
• Azithromycin 500 mg once daily for 5 days
• Clarithromycin extended-release 1000 mg once daily for 5–7 days

For severe AECB (FEV₁ <35%, frequent exacerbations, multiple comorbidities): 4, 5, 6

• Amoxicillin-clavulanate 625 mg three times daily for 14 days
• Respiratory fluoroquinolone (levofloxacin 750 mg once daily for 5 days)

Critical Pitfalls to Avoid

• Do NOT use simple amoxicillin monotherapy—25% of H. influenzae and 50–70% of M. catarrhalis produce β-lactamase, rendering it ineffective 4, 7
• Do NOT prescribe antibiotics based on sputum color alone—purulent sputum occurs in 89–95% of viral cases 2, 4
• Obtain sputum culture when possible before starting empirical antibiotics, then adjust therapy based on sensitivities if no clinical improvement occurs at 2–3 days 4

Supportive Therapy During Exacerbations

• Systemic corticosteroids (prednisone 40 mg daily for 5–7 days or equivalent) improve lung function, oxygenation, and shorten recovery time during acute exacerbations 3, 4
• Short-acting β₂-agonists and/or anticholinergics (ipratropium) are recommended during exacerbations 1, 3
• Do NOT use theophylline during acute exacerbations 4
• Do NOT use postural drainage or chest percussion during exacerbations—no proven benefit 1, 3

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Special Considerations for Elderly Patients

• Elderly patients often present with atypical pneumonia (lower prevalence of respiratory symptoms); maintain a low threshold for chest imaging 4
• High-risk comorbidities lower the threshold for initiating antibiotics in AECB in elderly patients 4, 5
• After initiating antibiotics for AECB, perform clinical review at 2–3 days; lack of improvement should prompt sputum culture and targeted therapy adjustment 4