Abnormally increased nasal mucus secretion that drips down the back of the throat and can lead to coughing, a feeling of obstruction in the throat, and throat clearing.
- Epidemiology & Risk Factors
- Formerly known as “postnasal drip syndrome.”
- #1 cause of chronic cough (>8 wks) in adults.
- Etiologies: Allergic rhinitis, nonallergic vasomotor rhinitis, acute/chronic rhinosinusitis, environmental irritants.
- Clinical Features
- Chronic cough (often worse at night or upon awakening).
- Frequent throat clearing (“tickle” in the back of the throat).
- Rhinorrhea, nasal congestion.
- PE: Cobblestone appearance of posterior pharyngeal mucosa (due to lymphoid hyperplasia).
- PE: Mucoid or purulent secretions in posterior pharynx.
- Diagnosis
- Initial/Screening: Clinical Hx & PE.
- Confirmatory/Gold Standard: Clinical diagnosis confirmed by resolution of cough w/ empiric therapy.
- Imaging: Sinus CT only indicated if concern for chronic sinusitis or if refractory to initial empiric management.
- Differential Diagnostics
- Asthma (Cough-Variant): Diff by wheezing, dyspnea, (+) response to bronchodilators, or (+) methacholine challenge. Normal pharyngeal exam.
- GERD: Diff by heartburn, water brash, dysphagia. Cough often worse post-prandially or supine. Resolves w/ PPI trial.
- ACE Inhibitor Cough: Diff by medication Hx. Caused by bradykinin accumulation. Resolves 1-4 wks post-discontinuation.
- Bronchiectasis: Diff by large volume purulent sputum, recurrent respiratory infxns, crackles on auscultation. Dx w/ HRCT.
- Management
- First-line (Empiric Trial): Oral 1st-generation antihistamine/decongestant combo (e.g., chlorpheniramine + pseudoephedrine). Note: 1st-gen antihistamines are preferred over 2nd-gen due to stronger anticholinergic effects which dry up secretions.
- Targeted Therapy (if allergic rhinitis confirmed): Intranasal corticosteroids (e.g., fluticasone) +/- 2nd-gen antihistamines (e.g., cetirizine).
- Refractory/Sinusitis: If pt has purulent nasal d/c or sinus pain >10 days, consider Abx for acute bacterial rhinosinusitis (e.g., Amoxicillin-clavulanate).