Upper airway cough syndrome
Upper airway cough syndrome, formerly called postnasal drip syndrome, is chronic cough driven by postnasal drainage from allergic rhinitis, nonallergic rhinitis, or chronic sinusitis, and is one of the three most common causes of chronic cough alongside GERD and asthma. It is diagnosed clinically and confirmed by response to an empiric trial of therapy directed at the underlying rhinitis or sinusitis subtype.
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What this article covers
- Overview
A syndrome, not a standalone disease: upper airway cough syndrome (UACS), formerly postnasal drip syndrome, is chronic cough from postnasal drainage; it always has an underlying driver, most often…
- Epidemiology
Common in the chronic cough population: UACS is one of the most frequently identified causes when patients are worked up for chronic cough, alongside GERD and asthma.
- Risk factors
Allergic rhinitis: IgE-mediated type 1 hypersensitivity of the nasal mucosa; intermittent/seasonal (grass, tree, pollen) or persistent/perennial (dust, dust mites, mold, pets) patterns, often with a personal or family history of atopy.
- Pathophysiology
Postnasal drainage irritates the upper airway: the cough of UACS is precipitated by postnasal drainage of nasal and sinus secretions into the pharynx and larynx, distinguishing its mechanism from the bronchial hyperreactivity of asthma.
- Clinical features
Chronic cough is the defining and often only symptom: UACS manifests as cough of more than 8 weeks (or, in the postinfectious subacute setting, 3 to 8 weeks), and this cough establishes the…
- Differential diagnosis
Asthma (including cough-variant asthma): wheeze or dyspnea, unlike UACS which by definition has neither; spirometry shows reversible obstruction or bronchial provocation testing is positive, and…
- Diagnosis
UACS is a clinical diagnosis confirmed by response to targeted empiric treatment: established by chronic (or postinfectious subacute) cough without wheeze or shortness of breath, with symptoms or…
- Management
First, treat the underlying cause, not the cough itself: UACS management targets the specific rhinitis or sinusitis subtype identified, with no UACS-specific antitussive step ahead of that.
- Complications
Rhinitis medicamentosa: overuse of a topical nasal decongestant beyond 3 to 6 days causes rebound congestion that perpetuates postnasal symptoms.
- Prognosis
Good with correctly targeted therapy: UACS responds to treatment directed at its underlying cause, and cough improvement over the 2-week empiric trial both treats the condition and corroborates the diagnosis.
- Prevention
Limit topical decongestant use to 3 to 6 days per course to prevent rhinitis medicamentosa; if longer decongestion is needed, transition to an intranasal corticosteroid, which does not cause this dependence.
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Related articles
- Allergic rhinitis
Allergic rhinitis is an IgE-mediated inflammation of the nasal mucosa causing sneezing, rhinorrhea, congestion, and itch on allergen exposure, classified as seasonal or perennial. Diagnosis is clinical, supported by skin or specific IgE testing to identify allergens, and treatment is allergen avoidance with intranasal corticosteroids first-line, escalating to combination therapy and allergen immunotherapy.
- Chronic rhinosinusitis
Chronic rhinosinusitis is inflammation of the paranasal sinuses lasting 12 weeks or longer, confirmed by nasal endoscopy or CT, and treated first with intranasal corticosteroids and saline irrigation before escalation to antibiotics, oral steroids, biologics, or surgery.
- Acute rhinosinusitis
Acute rhinosinusitis is inflammation of the nasal cavity and paranasal sinuses lasting up to 4 weeks, presenting with purulent nasal discharge plus nasal obstruction or facial pain/pressure/fullness. Most cases are viral and treated with acetaminophen/ibuprofen plus nasal saline irrigation alone; a minority are bacterial, identified by persistence beyond 10 days, a biphasic worsening course, or severe onset, and treated with amoxicillin-clavulanate 875/125 mg PO every 12 hours for 5 to 7 days.
- Asthma
Asthma is a chronic inflammatory airway disorder causing episodic, reversible airflow obstruction confirmed by spirometry or bronchial challenge testing. Management is a stepwise ladder led by inhaled glucocorticoids plus as-needed SABA or ICS-formoterol, escalating to biologics for severe type 2-high disease, with an oral glucocorticoid burst and frequent SABA for exacerbations.
- Gastroesophageal reflux disease (GERD)
GERD is retrograde reflux of gastric contents into the esophagus causing heartburn and regurgitation, diagnosed clinically and confirmed by response to an empiric PPI trial, with endoscopy reserved for alarm features or refractory symptoms. Management proceeds from lifestyle measures through an 8-week once-daily PPI trial, dose escalation or agent switch for partial response, and fundoplication for medication-refractory or regurgitation-predominant disease.
- Chronic cough
Chronic cough, defined as cough lasting more than 8 weeks, is most often caused by upper airway cough syndrome, asthma, gastroesophageal reflux disease (GERD), nonasthmatic eosinophilic bronchitis, smoking, or ACE inhibitor use, frequently in combination. Evaluation is a stepwise sequence of history, examination, and chest radiography followed by sequential empiric treatment trials, reserving cross-sectional imaging and bronchoscopy for red flags or treatment failure.
- Nasal polyps
Nasal polyps are benign, typically bilateral outgrowths of edematous nasal mucosa driven by chronic mucosal inflammation, most often arising with chronic rhinosinusitis, aspirin-exacerbated respiratory disease, or cystic fibrosis. Unilateral polyps or a mass that does not respond to treatment must be biopsied to exclude tumor.