Medical Management of Postnasal Drip

Understanding Postnasal Drip

• Postnasal drip (PND) is the drainage of secretions from the nose or paranasal sinuses into the pharynx, now preferably termed Upper Airway Cough Syndrome (UACS), which is the most common cause of chronic cough in adults, characterized by symptoms including sensation of drainage in the throat, throat clearing, nasal discharge, and cobblestone appearance of the oropharyngeal mucosa 1, 2, 3
• Some patients may have "silent" PND with no obvious symptoms yet still respond to treatment 3

Treatment Algorithm Based on Underlying Cause

First-line Treatments

• For non-allergic rhinitis-related postnasal drip, the American College of Chest Physicians recommends first-generation antihistamine plus decongestant combination 4, 3
• For allergic rhinitis-related postnasal drip, treatment options include nasal corticosteroids, antihistamines, and/or cromolyn 3
• Effective first-generation antihistamine/decongestant combinations include dexbrompheniramine maleate plus sustained-release pseudoephedrine sulfate, and azatadine maleate plus sustained-release pseudoephedrine sulfate, with a minimum of 3 weeks of treatment recommended for chronic cases 3, 4

Nasal Corticosteroids

• Intranasal corticosteroids are effective for allergic rhinitis with postnasal drip and require a 1-month trial, as recommended by the British Thoracic Society 5, 3

Alternative Treatments

• Ipratropium bromide nasal spray is an effective alternative for patients who don't respond to antihistamine/decongestant combinations or have contraindications 3
• For rhinitis due to physical or chemical irritants, avoidance of exposure, improved ventilation, filters, and personal protective devices are effective, as suggested by the American College of Chest Physicians 4

Treatment for Specific Conditions

• For acute bacterial sinusitis, treatment options include antibiotics, intranasal corticosteroids, and decongestants, as recommended by the American College of Chest Physicians 4
• For chronic sinusitis, a minimum of 3 weeks of antibiotics effective against H. influenzae, mouth anaerobes, and S. pneumoniae; 3 weeks of oral antihistamine/decongestant; and 5 days of nasal decongestant are recommended, followed by 3 months of intranasal corticosteroids 4

Clinical Considerations and Monitoring

Expected Response

• Most patients will see improvement in cough within days to 2 weeks of initiating therapy, with the American College of Chest Physicians recommending to minimize sedation from first-generation antihistamines by starting with once-daily dosing at bedtime before increasing to twice-daily therapy 3

Side Effects to Monitor

• Common side effects of first-generation antihistamines include dry mouth and transient dizziness, while more serious side effects include insomnia, urinary retention, jitteriness, tachycardia, worsening hypertension, and increased intraocular pressure in glaucoma patients, as reported by the American College of Chest Physicians 3

Treatment Duration

• For allergic rhinitis with postnasal drip, a 1-month trial of intranasal corticosteroids is recommended by the British Thoracic Society 5, 3
• For chronic rhinitis conditions, longer treatment courses may be necessary, as suggested by the American College of Chest Physicians 3
• For chronic sinusitis, a minimum of 3 weeks of treatment followed by 3 months of intranasal corticosteroids is recommended by the American College of Chest Physicians 4

Common Pitfalls and Caveats

• Newer-generation antihistamines are less effective for non-allergic causes of postnasal drip cough, according to the American College of Chest Physicians 3
• The diagnosis of postnasal drip syndrome can be challenging as symptoms and clinical findings are not reliable discriminators, as noted by the British Thoracic Society 5
• Some patients with UACS-induced cough (approximately 20%) are unaware of either the presence of PND or its link to their cough, as reported by the American College of Chest Physicians 2
• Failure to consider "silent" UACS as a causative factor for chronic cough can lead to missed diagnoses, according to the American College of Chest Physicians 3
• Endoscopic sinus surgery should be considered only for patients with documented chronic sinus infection refractory to medical therapy and with anatomic obstruction, as recommended by the American College of Chest Physicians 4
• Post nasal drip can sometimes be confused with other conditions like gastroesophageal reflux disease (GERD), as noted by the American College of Chest Physicians 3

Best Treatment for Chronic Severe Post Nasal Drip

First-Line Treatment Options

• Intranasal corticosteroids are the most effective monotherapy for chronic post nasal drip, particularly when related to allergic or inflammatory causes, as recommended by the American Academy of Allergy, Asthma, and Immunology 6
• The American College of Allergy, Asthma, and Immunology recommends intranasal corticosteroids as the first choice for allergic rhinitis-related post nasal drip, with a recommended 1-month trial, and oral antihistamines may be added, though second-generation agents are generally preferred over first-generation to avoid sedation 6
• Long-term use of topical decongestants (>3-5 days) should be avoided as they can cause rhinitis medicamentosa, according to the American College of Chest Physicians 7
• Decongestants can cause side effects such as insomnia, irritability, palpitations, and hypertension, as reported by the American Academy of Allergy, Asthma, and Immunology 6

Treatment Options for Postnasal Phlegm Mucolysis

First-Line Treatment Algorithm

• The American Academy of Otolaryngology states that leukotriene blockers can decrease symptoms of allergic rhinitis 8

Second-Line and Adjunctive Options

• Guaifenesin has limited evidence for efficacy in postnasal drip despite its FDA indication to "help loosen phlegm (mucus) and thin bronchial secretions", according to the American Academy of Otolaryngology 9
• The American Academy of Otolaryngology states there is no evidence regarding guaifenesin's effect on symptomatic relief of acute bacterial rhinosinusitis 9

Critical Considerations and Pitfalls

• Topical decongestants should NEVER be used for more than 3-5 consecutive days due to risk of rhinitis medicamentosa (rebound congestion), as warned by the American Academy of Otolaryngology and the Journal of Allergy and Clinical Immunology 9, 10
• Antihistamines have no role in symptomatic relief for non-atopic patients and may worsen congestion by drying nasal mucosa, according to the American Academy of Otolaryngology 9

Special Populations

• For patients with allergic rhinitis and acute bacterial sinusitis, second-generation H1-antagonists combined with antibiotics and oral corticosteroids can reduce sneezing and nasal congestion, as recommended by the American Academy of Otolaryngology 9
• In pregnancy, caution is recommended with decongestants during the first trimester due to potential fetal heart rate changes, as advised by the Journal of Allergy and Clinical Immunology 10

Treatment for Underlying Sinusitis

• Watchful waiting without antibiotics is appropriate for uncomplicated cases of acute bacterial rhinosinusitis with assured follow-up, according to the American Academy of Otolaryngology 9