What is the treatment for a wet cough?

Treatment of Wet Cough

For children with chronic wet cough (>4 weeks) without warning signs, prescribe 2 weeks of antibiotics targeting common respiratory bacteria (Streptococcus pneumoniae, Haemophilus influenzae, Moraxella catarrhalis), specifically amoxicillin-clavulanate as first-line therapy. 1

Initial Assessment: Acute vs. Chronic

Determine cough duration first:

• Acute wet cough (<4 weeks): Supportive care only—no antibiotics initially 2, 3
• Chronic wet cough (>4 weeks): Antibiotics indicated 1

This distinction is critical because acute wet cough is typically viral and self-limiting, while chronic wet cough suggests protracted bacterial bronchitis (PBB) requiring antibiotic treatment. 1, 2

Acute Wet Cough Management (<4 weeks)

Provide supportive care exclusively:

• Adequate hydration to thin secretions 2
• Saline nasal drops for congestion 2
• Elevate head of bed during sleep 2
• Avoid over-the-counter cough medications in children under 6 years (ineffective and potentially harmful) 2
• Never use honey in infants <12 months (botulism risk) 2, 3

Do NOT prescribe antibiotics initially for transparent sputum without fever—this presentation indicates viral infection. 2, 3

When to Start Antibiotics in Acute Phase

Antibiotics become appropriate only if:

• Symptoms persist >10 days without improvement 2
• Symptoms worsen after initial improvement 2
• Severe onset with fever ≥39°C (102.2°F) plus purulent nasal discharge for ≥3 consecutive days 2

Chronic Wet Cough Management (>4 weeks)

First-Line Treatment

Prescribe 2 weeks of amoxicillin-clavulanate (45 mg/kg/day divided every 12 hours for moderate-to-severe infection). 1, 2 This is the most commonly studied antibiotic in prospective trials and covers the three primary respiratory pathogens. 1

The CHEST guidelines provide Grade 1A evidence (the highest quality) for this recommendation, based on systematic reviews showing that antibiotics effectively resolve chronic wet cough in children without underlying disease. 1

If Cough Persists After 2 Weeks

Extend antibiotics for an additional 2 weeks (total 4 weeks of treatment). 1 This stepwise approach balances antimicrobial stewardship with treatment efficacy. 1

If Cough Persists After 4 Weeks Total

Refer for further investigation:

• Flexible bronchoscopy with quantitative cultures 1
• Chest CT scan (children with persistent cough after 4 weeks of antibiotics have 5.9-fold increased likelihood of bronchiectasis) 1
• Consider alternative diagnoses 1

Diagnosis of Protracted Bacterial Bronchitis

If chronic wet cough resolves within 2 weeks of appropriate antibiotics, diagnose PBB. 1 This is termed "clinically-based PBB" and does not require bronchoscopy confirmation in routine practice. 1

Lower airway microbiology (via BAL showing ≥10⁴ CFU/mL of respiratory bacteria) confirms "microbiologically-based PBB," but this is not necessary for diagnosis when clinical response occurs. 1

Red Flags Requiring Immediate Investigation

Do NOT use the standard antibiotic approach if specific "cough pointers" are present:

• Coughing with feeding (suggests aspiration) 1, 2
• Digital clubbing (suggests chronic lung disease) 1
• Failure to thrive 4
• Respiratory distress (retractions, grunting, cyanosis) 2, 3

These children require immediate referral for:

• Flexible bronchoscopy and/or chest CT 1
• Aspiration assessment 1
• Immunologic evaluation 1

Special Considerations for Infants

Infants <12 months require heightened vigilance:

• Respiratory rate >70 breaths/min mandates immediate attention 3, 4
• Consider pertussis in any infant with paroxysmal cough, especially with post-tussive vomiting or inspiratory "whoop" 2, 3
• Unvaccinated/incompletely vaccinated infants have highest risk for life-threatening pertussis complications 3

Role of Expectorants and Cough Suppressants

Guaifenesin and dextromethorphan are NOT recommended for wet cough in children. 2 While guaifenesin is FDA-approved to "help loosen phlegm" 5, and has some evidence in chronic bronchitis in adults 6, 7, there is no quality evidence supporting its use in pediatric wet cough. The American Academy of Pediatrics explicitly advises against OTC cough medications in children under 6 years. 2

Dextromethorphan is a cough suppressant 8, which is counterproductive in wet cough where expectoration is therapeutic. 9

Common Pitfalls to Avoid

• Do not prescribe antibiotics for acute wet cough <4 weeks duration unless specific criteria are met 2
• Do not stop antibiotics at 1 week—minimum 2-week course is required 1
• Do not delay investigation beyond 4 weeks of failed antibiotic therapy—risk of underlying bronchiectasis increases 1
• Do not miss "cough pointers" that indicate need for immediate investigation rather than empiric antibiotics 1