What antibiotics are recommended for an outpatient with bronchitis (bronchitis), considering the likely cause and patient's symptoms, medical history, and potential allergies or interactions with other medications?

Antibiotics for Outpatient Bronchitis

Do not prescribe antibiotics for acute bronchitis in otherwise healthy adults—they provide no meaningful clinical benefit while causing significant adverse effects and contributing to antibiotic resistance. 1, 2

Initial Assessment: Rule Out Conditions That Actually Need Treatment

Before diagnosing simple acute bronchitis, you must exclude pneumonia and other conditions requiring specific therapy:

• Check vital signs immediately: Heart rate >100 bpm, respiratory rate >24 breaths/min, or oral temperature >38°C suggests pneumonia, not bronchitis 1, 2
• Examine the chest for focal findings: Rales, egophony, or tactile fremitus indicate pneumonia and warrant chest radiography 2
• Consider alternative diagnoses: Approximately one-third of patients diagnosed with "recurrent acute bronchitis" actually have undiagnosed asthma or COPD exacerbations 1, 2

If any of these red flags are present, you are not dealing with simple acute bronchitis—obtain chest imaging and manage accordingly. 2

The Evidence Against Antibiotics in Acute Bronchitis

Acute bronchitis is viral in 89-95% of cases, making antibiotics completely ineffective regardless of which agent you choose. 2, 3, 4

The 2020 CHEST Expert Panel reviewed all available evidence and found:

• Antibiotics reduce cough duration by only 0.5 days (approximately 12 hours) 1, 2, 4
• Antibiotics significantly increase adverse events (RR 1.20; 95% CI 1.05-1.36) 2
• No difference in clinical outcomes between antibiotic and placebo groups 1

Common Pitfalls That Lead to Inappropriate Prescribing

Pitfall #1: Purulent Sputum Does NOT Indicate Bacterial Infection

Purulent or green sputum occurs in 89-95% of viral bronchitis cases and is not an indication for antibiotics. 2, 3 This is caused by neutrophil peroxidase from the inflammatory response, not bacteria.

Pitfall #2: Cough Duration Does NOT Indicate Bacterial Infection

Viral bronchitis cough typically lasts 10-14 days, sometimes up to 3 weeks. 2, 3, 4 This normal duration does not justify antibiotic use.

Pitfall #3: Patient Expectation Should NOT Drive Prescribing

Patient satisfaction depends more on physician-patient communication quality than whether an antibiotic is prescribed. 2, 5 Explain the viral etiology, expected duration, and potential harms of unnecessary antibiotics. 2

What TO Do: Appropriate Management

Patient Education (Most Important Intervention)

• Inform patients that cough typically lasts 10-14 days after the visit, even without antibiotics 2, 3, 4
• Explain that the condition is self-limiting and resolves within 3 weeks 1, 4
• Refer to the condition as a "chest cold" rather than "bronchitis" to reduce antibiotic expectations 2, 4
• Discuss the risks of unnecessary antibiotic use: adverse effects (diarrhea, rash, allergic reactions) and contribution to antibiotic resistance 2

Symptomatic Treatment Options (Limited Efficacy)

• Antitussives (codeine or dextromethorphan): May provide modest relief for bothersome dry cough, especially when sleep is disturbed 2, 3
• β2-agonist bronchodilators: Use ONLY in select patients with accompanying wheezing—not routinely 1, 2
• Low-risk measures: Elimination of environmental cough triggers, vaporized air treatments 2

What NOT to Prescribe

The CHEST guidelines explicitly recommend against routine use of: 1

• Antibiotics
• Antiviral therapy
• Inhaled corticosteroids
• Oral corticosteroids
• Oral NSAIDs at anti-inflammatory doses
• Expectorants or mucolytics

The ONE Exception: Pertussis (Whooping Cough)

For confirmed or suspected pertussis, prescribe a macrolide antibiotic immediately:

• Azithromycin (preferred): 500 mg on day 1, then 250 mg daily for days 2-5 2
• Erythromycin (alternative): 500 mg four times daily for 14 days 2
• Isolate the patient for 5 days from the start of treatment to prevent disease spread 2
• Early treatment within the first few weeks diminishes coughing paroxysms and prevents transmission 2

When to Reassess: Red Flags for Worsening

Instruct patients to return if: 1, 2

• Fever persists >3 days: Strongly suggests bacterial superinfection or pneumonia
• Cough persists >3 weeks: Consider alternative diagnoses (asthma, COPD, pertussis, GERD)
• Symptoms worsen rather than gradually improve

At reassessment, if bacterial infection is now thought likely based on clinical deterioration, then consider targeted antibiotic therapy. 1

Special Populations: Different Rules Apply

These recommendations apply to immunocompetent adults with uncomplicated acute bronchitis. The following patients require different management: 2

• COPD or chronic bronchitis exacerbations: May need antibiotics if meeting Anthonisen criteria (increased dyspnea, sputum volume, or sputum purulence) 2, 6
• Immunocompromised patients: Lower threshold for antibiotics 2
• Elderly with comorbidities (cardiac failure, insulin-dependent diabetes): Consider antibiotics more readily 2, 6
• Patients with chronic respiratory insufficiency: May need immediate antibiotic therapy 2

Algorithm for Decision-Making

1. Check vital signs and examine chest → Abnormal? → Not simple bronchitis, obtain chest X-ray 1, 2
2. Normal vital signs and exam → Diagnose acute bronchitis
3. Suspect pertussis? (paroxysmal cough, post-tussive vomiting, inspiratory whoop) → Yes? → Prescribe macrolide 2
4. Uncomplicated acute bronchitis → No antibiotics 1, 2
5. Provide education on expected 10-14 day duration 2, 4
6. Offer symptomatic treatment (antitussives if bothersome dry cough) 2
7. Reassess if fever >3 days or cough >3 weeks 1, 2