What is the appropriate management for a 36-year-old male with a history of tobacco (nicotine) chewing and smoking, presenting with a dry cough that worsens when lying down on the right side, facial throat pain, and cough triggered by stimulation of the shaving area of the face, without dysphonia (voice disturbance) or dysphagia (swallowing difficulty)?

Urgent Evaluation for Possible Malignancy with Immediate Smoking Cessation

This patient requires urgent evaluation for head and neck malignancy, particularly given the highly concerning Arnold's nerve reflex (cough triggered by facial stimulation) combined with significant tobacco exposure, positional cough, and throat pain without dysphagia or dysphonia.

Critical Red Flags Present

This clinical presentation contains several alarming features that demand immediate investigation:

• Arnold's nerve reflex: Cough triggered by stimulation of the shaving area strongly suggests vagal nerve irritation, which can indicate laryngeal or hypopharyngeal pathology 1
• Significant tobacco exposure: Both smoking and chewing tobacco dramatically increase risk for upper aerodigestive tract malignancies 1
• Positional cough: Worsening when lying on the right side may indicate a mass effect or anatomical distortion 1
• Throat pain without dysphagia/dysphonia: Early malignancy may present with referred pain before causing functional impairment 1

Immediate Management Steps

1. Mandatory Smoking and Tobacco Cessation

• Counsel and assist with immediate cessation of both smoking and tobacco chewing 1, 2
• Smoking cessation typically resolves tobacco-related cough within 4 weeks, though it may take longer in some cases 1
• This is both diagnostic (if cough persists, other pathology is likely) and therapeutic 1

2. Urgent Diagnostic Workup

• Obtain chest radiograph immediately to evaluate for lung pathology, though normal findings do not exclude serious disease 1
• Refer urgently to ENT/head and neck surgery for direct laryngoscopy and hypopharyngoscopy to visualize the upper airway and evaluate for malignancy 1
• The Arnold's nerve reflex (auricular branch of vagus) suggests pathology in the larynx, hypopharynx, or external auditory canal that requires direct visualization 1

3. If Initial Chest X-ray is Normal

Do not be falsely reassured. The concerning features warrant:

• High-resolution CT scan of chest and neck with contrast to evaluate for occult masses, lymphadenopathy, or other structural abnormalities 1
• Consider bronchoscopy if imaging suggests airway involvement to look for endobronchial tumor or other occult airway disease 1

Common Causes to Consider (Only After Excluding Malignancy)

While the systematic approach to chronic cough typically starts with the most common causes, this patient's presentation is atypical and concerning enough to warrant deviation from the standard algorithm 1:

Upper Airway Cough Syndrome (UACS)

• If malignancy is excluded, consider empiric trial of first-generation antihistamine/decongestant combination 1, 2
• Response typically occurs within days to 1-2 weeks if UACS is the cause 1

Gastroesophageal Reflux Disease (GERD)

• Positional cough (worse lying down) could suggest GERD 1
• However, GERD typically does not cause the Arnold's nerve reflex 1
• If considered, initiate proton pump inhibitor with dietary/lifestyle modifications 1, 2
• Response may take 2 weeks to several months 1

Asthma/Bronchial Hyperresponsiveness

• Less likely given the specific trigger (facial stimulation) and positional nature 1
• If pursued, would require spirometry with bronchodilator response or bronchoprovocation challenge 2

Critical Pitfalls to Avoid

• Do not assume this is simple chronic bronchitis from smoking despite the tobacco history—the Arnold's nerve reflex is highly specific for vagal irritation 1
• Do not treat empirically for common causes without imaging and ENT evaluation first in this high-risk patient 1
• Do not delay investigation while waiting for smoking cessation to take effect—pursue both simultaneously 1
• Do not rely on normal chest radiograph to exclude serious pathology; HRCT and direct visualization may be necessary 1

Sequential Approach if Malignancy Excluded

Only after thorough evaluation excludes malignancy:

1. Continue tobacco cessation and reassess in 4 weeks 1
2. Trial of first-generation antihistamine/decongestant for possible UACS 1, 2
3. Trial of high-dose PPI therapy for possible GERD if positional symptoms persist 1, 2
4. Consider 24-hour esophageal pH monitoring if GERD suspected but not responding to empiric therapy 1
5. Bronchoscopy for occult airway disease if all above measures fail 1

The Arnold's nerve reflex in a heavy tobacco user is a red flag that cannot be ignored and requires urgent specialist evaluation before pursuing the standard chronic cough algorithm 1.