What is the best course of action for a 47-year-old female patient with a history of diabetes, hypertension, hypercholesterolemia, and pulmonary fibrosis, who presents with a persistent itchy throat, erythematous tonsils, and a history of temporary relief with Montelukast (montelukast), despite initial resolution of productive cough and yellowish phlegm?

Management of Persistent Itchy Throat in a Patient with Pulmonary Fibrosis

This patient requires immediate discontinuation of Montelukast and evaluation for post-infectious pharyngitis with consideration of her underlying pulmonary fibrosis status, followed by symptomatic treatment with first-generation antihistamine-decongestant therapy.

Primary Clinical Assessment

The presentation suggests a post-infectious pharyngitis following resolution of an acute respiratory infection, with the erythematous tonsils representing persistent upper airway inflammation 1. The 3-week timeline places this in the transition between acute and subacute cough (which extends to 8 weeks), and the gradual resolution except for throat irritation is consistent with post-infectious upper airway syndrome (UACS) 1.

Critical Consideration: Pulmonary Fibrosis Context

The history of pulmonary fibrosis requires urgent clarification - you must determine:

• Whether this is idiopathic pulmonary fibrosis (IPF) or secondary to connective tissue disease, as IPF typically presents with progressive exertional dyspnea and dry cough, not productive cough with yellowish phlegm 1
• The presence of productive cough with thick yellowish phlegm is inconsistent with typical IPF presentation, which characteristically involves dry cough and bibasilar inspiratory "Velcro" crackles 1, 2, 3
• If this represents connective tissue disease-associated ILD (CTD-ILD), the patient requires multidisciplinary evaluation by pulmonology and rheumatology 1

Immediate Management Steps

1. Discontinue Montelukast

Stop Montelukast immediately - while it provided temporary relief, this medication:

• Is indicated for asthma and allergic rhinitis, not for post-infectious pharyngitis 4
• Has experimental anti-fibrotic properties in research settings but is not recommended for pulmonary fibrosis treatment in clinical practice 5, 6, 7
• The temporary relief likely represents placebo effect or coincidental timing with natural disease resolution 1

2. Initiate First-Line Therapy for UACS

Prescribe a first-generation antihistamine-decongestant combination as the primary treatment:

• This is the recommended first-line approach for upper airway cough syndrome (UACS), which is the most common cause of chronic cough 1
• Expected response timeline: noticeable improvement within days to 1-2 weeks, with marked improvement or resolution taking several weeks to occasionally a few months 1
• The erythematous tonsils indicate ongoing upper airway inflammation that should respond to this therapy 1

3. Pulmonary Fibrosis Evaluation

Urgent assessment of pulmonary fibrosis status is required:

• Review prior imaging (HRCT chest) to confirm the diagnosis and pattern of fibrosis 1
• Investigate for connective tissue disease with appropriate serologic testing (ANA, RF, anti-CCP, anti-Ro/SSA, anti-Scl-70) given the atypical presentation with productive cough 1
• Exclude drug-induced ILD from current medications (Empagliflozin, Telmisartan, Atorvastatin) 1
• Perform pulmonary function tests if not recently done to assess disease severity and progression 1, 3

Algorithmic Approach to Persistent Symptoms

If symptoms persist after 2 weeks of antihistamine-decongestant therapy:

1. Add intranasal corticosteroid for persistent upper airway inflammation 1
2. Consider sinus imaging (CT or plain films) to evaluate for acute or chronic sinusitis if nasal symptoms persist 1
3. Evaluate for asthma with bronchoprovocation challenge if cough persists, as chronic cough is often multifactorial 1

If productive cough recurs or worsens:

• Obtain chest radiograph to exclude pneumonia, bronchiectasis, or progression of pulmonary fibrosis 1
• Consider HRCT chest if not recently performed, as bronchiectasis can present with chronic productive cough and coarse (not fine) crackles 1, 2

Critical Pitfalls to Avoid

Do not continue Montelukast - there is no evidence supporting its use for post-infectious pharyngitis or pulmonary fibrosis in clinical practice, despite experimental anti-fibrotic effects in animal models 5, 6, 7, 8, 9

Do not assume the pulmonary fibrosis diagnosis is accurate without reviewing imaging and excluding CTD-ILD, as the productive cough presentation is atypical for IPF 1, 2, 3

Do not delay evaluation of the underlying lung disease - if this represents progressive pulmonary fibrosis, early identification and treatment with antifibrotic therapy (pirfenidone or nintedanib for IPF) significantly impacts outcomes 1

Monitor for red flags including progressive dyspnea, hemoptysis, weight loss, or systemic symptoms that would warrant immediate chest imaging and pulmonary consultation 1, 3