What could be causing my persistent sore throat, nasal congestion, and dry cough, with associated pains, that hasn't improved with Dayquil (acetaminophen/dextromethorphan) and hot tea?

Persistent Sore Throat with Nasal Congestion and Dry Cough

Your symptoms lasting 2 weeks with nasal congestion, dry cough, sore throat, and right-sided mandibular pain most likely represent upper airway cough syndrome (post-nasal drip) that requires treatment with a first-generation antihistamine/decongestant combination plus intranasal corticosteroids, with consideration for bacterial sinusitis given the mandibular pain and prolonged duration. 1

Diagnostic Considerations

Your symptom complex points to several key diagnostic possibilities:

Upper Airway Cough Syndrome (Most Likely)

• Nasal congestion with dry cough persisting beyond 10-14 days is the hallmark of upper airway cough syndrome (UACS), formerly called post-nasal drip syndrome. 2, 1
• The right-sided mandibular pain with palpation suggests possible sinusitis involvement, as facial-dental pain is a prominent symptom of bacterial sinusitis. 2
• UACS is the most common cause of chronic cough in adults and can present with or without obvious drainage sensations ("silent" post-nasal drip occurs in approximately 20% of cases). 1
• Your symptoms persisting beyond 10-14 days raise concern for bacterial sinusitis rather than simple viral upper respiratory infection. 2

Why DayQuil Hasn't Worked

• DayQuil contains acetaminophen and dextromethorphan, which only provide symptomatic relief but do not address the underlying inflammatory process causing your symptoms. 2
• Dextromethorphan at standard over-the-counter doses is often subtherapeutic for adequate cough suppression. 3
• Neither ingredient treats the nasal inflammation or post-nasal drainage that is perpetuating your cough. 2

Recommended Treatment Algorithm

First-Line Treatment (Start Immediately)

1. First-Generation Antihistamine/Decongestant Combination

• This is the most effective first-line treatment for UACS according to the American College of Chest Physicians. 1
• Specific effective combinations include dexbrompheniramine maleate plus sustained-release pseudoephedrine sulfate, or azatadine maleate plus sustained-release pseudoephedrine sulfate. 1
• Start with once-daily dosing at bedtime for a few days to minimize sedation, then increase to twice-daily if tolerated. 1
• Common side effects include dry mouth and transient dizziness; monitor for insomnia, urinary retention, jitteriness, tachycardia, or worsening hypertension. 1

2. Intranasal Corticosteroid

• Add fluticasone 100-200 mcg daily (or equivalent intranasal steroid) for a 1-month trial. 2, 1
• Intranasal steroids are effective for both allergic and non-allergic rhinitis-related UACS. 1
• This addresses the underlying nasal inflammation that perpetuates post-nasal drainage. 2

Evaluation for Bacterial Sinusitis

Given your right-sided mandibular pain with palpation and symptoms persisting 2 weeks:

• Your clinical profile suggests possible bacterial sinusitis, which requires antibiotic therapy in approximately 29% of cases with mucosal thickening. 1
• Prominent symptoms of bacterial sinusitis include persistent purulent rhinorrhea, facial-dental pain, postnasal drainage, and pain with palpation—several of which you have. 2
• If you develop purulent nasal discharge, worsening facial pain, or fever, you should be evaluated for bacterial sinusitis requiring antibiotics. 2

Expected Timeline for Improvement

• Most patients see improvement in cough within days to 2 weeks of initiating antihistamine/decongestant plus intranasal steroid therapy. 1
• If no improvement occurs within 2 weeks, proceed to evaluate for other causes including gastroesophageal reflux disease (GERD) or asthma variants. 1

Alternative Considerations if Initial Treatment Fails

Gastroesophageal Reflux Disease (GERD)

• GERD causes 5-41% of chronic cough cases and can be confused with post-nasal drip. 2
• Your pain with swallowing could represent either pharyngeal inflammation from post-nasal drip or esophageal reflux. 2
• If symptoms persist despite adequate upper airway treatment for 2 weeks, start omeprazole 20-40 mg twice daily before meals for at least 8 weeks. 2

Asthma or Eosinophilic Bronchitis

• Dry cough can represent cough-variant asthma, though you lack wheezing or shortness of breath. 2
• This would require inhaled corticosteroids if suspected after ruling out UACS and GERD. 2

Critical Pitfalls to Avoid

Do not continue relying on DayQuil alone—it provides only temporary symptomatic relief without addressing the underlying inflammatory process. 2, 3

Do not use newer-generation non-sedating antihistamines (like loratadine or cetirizine) as first-line therapy—they are less effective for non-allergic UACS because they lack the anticholinergic drying properties of first-generation antihistamines. 1

Do not ignore the right-sided mandibular pain—this suggests possible sinusitis that may require antibiotics if purulent discharge develops or symptoms worsen. 2

Do not assume treatment failure after only a few days—intranasal steroids require up to 1 month for full effect, and antihistamine/decongestant combinations typically show benefit within days to 2 weeks. 2, 1

When to Seek Urgent Evaluation

Seek immediate medical attention if you develop:

• High fever (suggesting bacterial infection requiring antibiotics) 2
• Severe worsening of facial pain or swelling 2
• Visual changes or severe headache (suggesting complications of sinusitis) 2
• Difficulty breathing or swallowing 2