What is the diagnosis and treatment for chronic cough, nasal congestion, and watery eyes?

Chronic Upper Airway Cough Syndrome (UACS) Secondary to Allergic Rhinitis

This 45-year-old woman most likely has Upper Airway Cough Syndrome (UACS) due to allergic rhinitis, and should be started immediately on a first-generation antihistamine plus decongestant combination (such as dexbrompheniramine with sustained-release pseudoephedrine) for a minimum of 3 weeks. 1, 2

Diagnosis

The constellation of chronic cough (>4 weeks), nasal congestion, and watery eyes strongly suggests allergic rhinitis causing UACS (previously called postnasal drip syndrome). 1

Key Diagnostic Features Supporting Allergic Rhinitis:

• Watery eyes (lacrimation) is highly specific for allergic rhinitis rather than nonallergic causes 1
• The triad of nasal congestion, rhinorrhea, and ocular symptoms occurs in up to 94% of allergic rhinitis patients 3
• Sneezing and extranasal involvement (itching of eyes) are more common to allergic rhinitis than other forms of rhinitis 1

Critical Diagnostic Pitfall:

"Silent" UACS can cause chronic cough without obvious postnasal drip sensation—approximately 20% of patients with UACS-induced cough are unaware of the connection between their postnasal drainage and cough. 1, 2 This is why empiric treatment trials are essential even when symptoms seem minimal. 1

Treatment Algorithm

First-Line Therapy (Start Immediately):

For UACS-induced cough, initiate a first-generation antihistamine/decongestant combination such as: 1, 2

• Dexbrompheniramine maleate plus sustained-release pseudoephedrine sulfate, OR
• Azatadine maleate plus sustained-release pseudoephedrine sulfate

Dosing strategy to minimize sedation: Start with once-daily dosing at bedtime, then increase to twice-daily if needed after several days. 2

Treatment duration: Minimum 3 weeks for chronic cases, as most patients see improvement within days to 2 weeks. 2

Why First-Generation Antihistamines Are Superior:

Newer-generation nonsedating antihistamines are ineffective for UACS-induced cough and should NOT be used. 1, 2 First-generation antihistamines have direct peripheral effects on histamine receptors and some central cough-suppressing activity that newer agents lack. 1

Second-Line Therapy (If Inadequate Response After 3 Weeks):

Add intranasal corticosteroid (fluticasone propionate 50 mcg, 1-2 sprays per nostril once daily): 2, 4

• Requires a 1-month trial to assess full efficacy 2
• Relieves nasal congestion, itchy/watery eyes, runny nose, sneezing 4
• Works by blocking multiple inflammatory mediators (histamine, prostaglandins, cytokines, leukotrienes) 4

The combination of intranasal antihistamine plus intranasal corticosteroid provides greater symptomatic relief than monotherapy. 5, 6

Alternative Option (If Contraindications to Antihistamine/Decongestant):

Ipratropium bromide nasal spray is effective for vasomotor symptoms and excessive watery secretions. 1

Confirming the Diagnosis

When to Consider Allergy Testing:

Skin testing or serum-specific IgE testing should be performed if: 1

• Inadequate response to empiric treatment after 4 weeks
• Diagnosis remains uncertain
• Need to guide allergen immunotherapy

Common allergens to test: 1

• Perennial (year-round): House dust mite (Dermatophagoides farinae/pteronyssinus), animal danders, indoor mold, cockroach
• Seasonal: Grass pollen, tree pollen, ragweed

Physical Examination Findings:

• Allergic rhinitis: Pale, edematous nasal turbinates (seasonal) or erythematous turbinates with serous secretions (perennial) 3
• Allergic shiners (dark circles under eyes), conjunctival swelling, clear rhinorrhea 7
• Cobblestone appearance of oropharyngeal mucosa suggests chronic postnasal drainage 2

Differential Diagnosis to Exclude

Other Causes of UACS: 1

• Perennial nonallergic rhinitis (vasomotor rhinitis): Watery secretions triggered by odors, temperature changes, eating—but no watery eyes (key distinguishing feature)
• NARES (nonallergic rhinitis with eosinophilia): Similar to vasomotor but with nasal/ocular pruritus and eosinophils in nasal secretions
• Postinfectious rhinitis: History of recent upper respiratory infection
• Bacterial sinusitis: Mucopurulent discharge, facial pain/pressure, may require sinus imaging if suspected 1

When to Obtain Sinus Imaging:

If patient fails to respond to empiric antihistamine/decongestant therapy, obtain sinus CT to evaluate for chronic sinusitis. 1 Chronic sinusitis can be "clinically silent" with nonproductive cough and no typical acute sinusitis findings. 1

GERD Can Mimic UACS:

Gastroesophageal reflux disease frequently presents with upper respiratory symptoms and may be confused with UACS. 1 If cough persists after treating UACS and asthma has been excluded, initiate empiric GERD therapy. 1

Monitoring and Expected Response

Timeline for Improvement:

• Most patients improve within days to 2 weeks of starting first-generation antihistamine/decongestant 2
• Intranasal corticosteroids require several days to reach maximum effect 4
• Continue treatment as long as exposed to allergens (may be seasonal or year-round depending on triggers) 4

Common Side Effects to Counsel: 2

• Antihistamines: Dry mouth, transient dizziness, sedation
• Decongestants: Insomnia, urinary retention, jitteriness, tachycardia, worsening hypertension, increased intraocular pressure in glaucoma patients
• Intranasal corticosteroids: Generally well-tolerated; long-term use in children may slow growth rate 4

When to Refer:

If cough remains undiagnosed or unresponsive after systematic treatment of UACS, asthma, and GERD, refer to a cough specialist. 1

Critical Pitfalls to Avoid

1. Failing to consider "silent" UACS as a cause of chronic cough before pursuing extensive workup for rare causes 1, 2

2. Using second-generation antihistamines for UACS-induced cough—they are ineffective for this indication 1, 2

3. Not treating empirically when diagnosis is uncertain—response to therapy is the pivotal factor in confirming UACS diagnosis 1

4. Stopping treatment when symptoms improve—continue as long as allergen exposure persists 4

5. Confusing allergic rhinitis with nonallergic rhinitis—the presence of watery eyes strongly favors allergic etiology 1

6. Using topical nasal decongestants >3-5 days—causes rhinitis medicamentosa (rebound congestion) 2