What is the next best step for a 40-year-old patient with a persistent cough producing yellow phlegm for 7 weeks, accompanied by a runny nose and ear blockage, who has not responded to amoxicillin (amoxicillin) and has no sore throat, epigastric pain, or chest pains?

Persistent Productive Cough After Failed Amoxicillin: Next Steps

This is most likely a post-viral upper airway cough syndrome (UACS) or subacute cough following viral upper respiratory infection, not bacterial sinusitis requiring antibiotics. 1

Why This Is Probably NOT Bacterial Sinusitis

Your clinical presentation does not meet criteria for acute bacterial rhinosinusitis (ABRS), which requires one of three specific patterns 2:

• Persistent symptoms ≥10 days without improvement (you have 7 weeks, but this suggests chronic process, not acute bacterial)
• Severe symptoms: fever >39°C with purulent nasal discharge for ≥3 consecutive days (you have no fever mentioned)
• "Double sickening": worsening after initial improvement (not clearly described here)

Critical point: Yellow/green phlegm does NOT indicate bacterial infection—it simply reflects neutrophils from inflammation, which occurs in viral infections too 1. The British Thoracic Society explicitly states that most short-term coughs are viral even when producing colored phlegm 1.

Most Likely Diagnosis: Post-Viral Cough

At 7 weeks duration, this is a subacute cough (3-8 weeks) 2. The typical viral upper respiratory infection causes cough that can persist for up to 3 weeks, and post-infectious cough can extend beyond this 1. Your constellation of symptoms—runny nose, ear blockage (eustachian tube dysfunction), productive cough without fever or systemic illness—strongly suggests ongoing post-viral upper airway inflammation rather than bacterial infection 1, 3.

Recommended Treatment Approach

First-Line Therapy (Start Immediately)

1. First-generation antihistamine/decongestant combination 2, 1

• This is the evidence-based first-line approach for upper airway cough syndrome
• Examples: chlorpheniramine-pseudoephedrine combinations
• Addresses both the runny nose and post-nasal drip driving the cough

2. Intranasal corticosteroid 1, 4

• Mometasone, fluticasone, or budesonide twice daily
• Reduces mucosal inflammation in nasal passages and sinuses
• Should be added since symptoms have persisted beyond one week 1

3. Intranasal ipratropium bromide 1

• May attenuate post-infectious cough
• Particularly helpful for persistent rhinorrhea

Symptomatic Relief

• Dextromethorphan-containing cough suppressants for nighttime cough relief 1
• Honey and lemon as home remedy 1
• Saline nasal irrigation to clear secretions 2, 4

When to Consider Antibiotics

DO NOT start another antibiotic course unless you develop 2, 1:

• High fever (>39°C) with purulent discharge for ≥3 consecutive days
• Significant worsening after initial improvement
• Severe unilateral facial pain/pressure with purulent discharge
• Symptoms that worsen rather than gradually improve

If antibiotics become necessary, the appropriate choice would be high-dose amoxicillin-clavulanate (875 mg/125 mg twice daily for 5-10 days), NOT plain amoxicillin, since you already failed amoxicillin 4. The clavulanate component covers β-lactamase-producing organisms (H. influenzae, M. catarrhalis) that plain amoxicillin misses 4, 5.

Red Flags Requiring Urgent Evaluation

Return immediately if you develop 1:

• Hemoptysis (coughing blood)
• Shortness of breath or wheezing
• High fever (>39°C)
• Severe worsening of symptoms
• Orbital symptoms: eye swelling, vision changes, severe headache (suggests complications)

Expected Timeline

• Most post-viral coughs resolve within 3 weeks, though some persist up to 8 weeks 1
• You should experience noticeable improvement within 5-7 days of starting the antihistamine/decongestant and intranasal corticosteroid regimen 1
• If no improvement after 3 weeks total (you're at 7 weeks now, so reassess in 1 week), consider evaluation for chronic cough causes: asthma, gastroesophageal reflux disease (GERD), or chronic rhinosinusitis 2

Why Amoxicillin Didn't Help

The failure of amoxicillin strongly suggests this was never bacterial sinusitis in the first place 1, 6. Even in true bacterial sinusitis, 80-86% of patients improve without antibiotics within two weeks 2, 6. The number needed to treat with antibiotics for bacterial sinusitis is 18 for one additional cure, while the number needed to harm from antibiotic side effects is only 8 2.

Critical Pitfall to Avoid

Do not take another course of antibiotics without meeting specific bacterial sinusitis criteria. Repeated antibiotic courses for viral upper respiratory symptoms contribute to antimicrobial resistance without clinical benefit and expose you to unnecessary side effects 2, 1, 6. The evidence shows that 98-99.5% of acute rhinosinusitis cases are viral and resolve spontaneously 2, 4.