In an otherwise healthy adult with a cough producing green‑yellow sputum, no fever or chills, mild throat irritation, and no wheezing, what is the most likely diagnosis and appropriate management?

Acute Viral Bronchitis (Chest Cold)

This presentation is classic for acute viral bronchitis and does not require antibiotics. Green sputum in the absence of fever, abnormal vital signs, or focal chest findings is a hallmark of viral lower respiratory tract infection, not bacterial infection, and antibiotics provide no meaningful benefit while exposing you to side effects. 1, 2

Why This Is Viral Bronchitis, Not Bacterial Infection

• Respiratory viruses cause 89–95% of acute bronchitis cases, making this the overwhelmingly most likely diagnosis in your presentation. 1, 2, 3
• Green or purulent sputum occurs in 89–95% of viral bronchitis and reflects inflammatory cells (neutrophils), not bacteria—sputum color does not distinguish viral from bacterial infection. 1, 2, 3
• Absence of fever, tachycardia (heart rate >100), tachypnea (respiratory rate >24), or abnormal lung exam makes pneumonia extremely unlikely and confirms this is uncomplicated bronchitis. 1, 2, 4

What You Should Expect

• Your cough will typically last 10–14 days and may persist up to 3 weeks even with perfect management—this is the natural course of viral bronchitis. 1, 2, 3
• The mild throat discomfort is part of the upper respiratory viral syndrome that often accompanies acute bronchitis. 5

Recommended Management: Symptomatic Relief Only

What Works (Modest Benefit)

• First-generation antihistamine plus decongestant (e.g., brompheniramine with pseudoephedrine) can reduce cough severity and hasten resolution by a few days. 6
• Naproxen may favorably affect cough symptoms. 6
• Antitussives (codeine or dextromethorphan) provide modest relief for bothersome dry cough, especially if it disrupts sleep. 1, 4
• Adequate hydration and removal of environmental irritants (dust, smoke) are low-risk supportive measures. 1, 6

What Does NOT Work (Avoid These)

• Antibiotics shorten cough by only 0.5 days (12 hours) while significantly increasing adverse effects (diarrhea, rash, yeast infections) and contributing to antibiotic resistance. 1, 2, 7
• Inhaled bronchodilators (albuterol) should only be used if you develop wheezing—you currently have no wheeze, so this is not indicated. 1, 4
• Inhaled or oral corticosteroids, expectorants, mucolytics, and NSAIDs at anti-inflammatory doses have no proven benefit in acute bronchitis. 1, 2

When to Seek Further Evaluation (Red Flags)

Return for reassessment if any of these develop:

• Fever persisting >3 days (suggests possible bacterial superinfection or pneumonia). 1, 6, 2
• Cough persisting >3 weeks (consider other diagnoses: asthma, pertussis, chronic conditions). 1, 6, 2
• Development of shortness of breath at rest, chest pain, or worsening symptoms rather than gradual improvement. 6, 2
• Hemoptysis (coughing blood), unintentional weight loss, or night sweats. 6

Special Consideration: Pertussis Exception

• If you develop paroxysmal coughing fits with post-tussive vomiting or an inspiratory "whoop," this suggests pertussis (whooping cough), which requires immediate macrolide antibiotic treatment (azithromycin or erythromycin) and isolation for 5 days. 1, 6, 3

Common Pitfalls to Avoid

• Do not assume green sputum means you need antibiotics—this is the most common misconception; 89–95% of viral bronchitis produces purulent-appearing sputum. 1, 2, 3
• Do not expect antibiotics to shorten your illness meaningfully—the 0.5-day reduction in cough is clinically insignificant compared to the 10–14 day natural course. 1, 2, 7
• Do not confuse this with pneumonia—your normal vital signs and absence of focal chest findings make pneumonia extremely unlikely. 1, 2, 4