What is the best management for post nasal drip?

Best Management for Post Nasal Drip

Start with a first-generation antihistamine/decongestant combination (such as dexbrompheniramine plus sustained-release pseudoephedrine or azatadine plus sustained-release pseudoephedrine) as first-line therapy, as this is the most effective initial treatment for post nasal drip regardless of whether the cause is allergic or non-allergic rhinitis. 1

Understanding the Condition

Post nasal drip is now preferably termed Upper Airway Cough Syndrome (UACS) and represents the most common cause of chronic cough in adults. 2, 1 The diagnosis is challenging because:

• No objective test exists to quantify post nasal drip or prove it causes symptoms 2
• Approximately 20% of patients have "silent" post nasal drip with no obvious symptoms yet still respond to treatment 1, 3
• Response to specific therapy remains the pivotal diagnostic factor 1

First-Line Treatment Algorithm

Initial Therapy (Days 1-14)

Begin with first-generation antihistamine/decongestant combinations: 1

• Dexbrompheniramine maleate plus sustained-release pseudoephedrine sulfate, OR 1
• Azatadine maleate plus sustained-release pseudoephedrine sulfate 1

Dosing strategy to minimize side effects: Start with once-daily dosing at bedtime for a few days before increasing to twice-daily therapy to reduce sedation. 1

Expected response: Most patients improve within days to 2 weeks. 1

If No Response After 1-2 Weeks

Add intranasal corticosteroids (fluticasone 100-200 mcg daily) for a 1-month trial, particularly if allergic rhinitis is suspected. 1, 3 A single randomized controlled trial demonstrated that intranasal steroids given for 2 weeks are effective in allergic rhinitis-related cough. 1

Alternative for Patients with Contraindications

Use ipratropium bromide nasal spray (42 mcg per spray, 2 sprays per nostril 4 times daily) for patients who cannot tolerate antihistamine/decongestant combinations due to hypertension, cardiovascular disease, or other contraindications. 1, 3 This provides anticholinergic drying effects without systemic cardiovascular side effects. 1

Treatment Based on Underlying Cause

Allergic Rhinitis

• First-line: Nasal corticosteroids, antihistamines, and/or cromolyn 1
• Oral leukotriene inhibitors decrease symptoms of allergic rhinitis 1, 3
• Intranasal antihistamines (azelastine or olopatadine) can be added for refractory cases 1, 4

Non-Allergic Rhinitis

• First-line: Older-generation antihistamine plus decongestant combination 1
• Critical distinction: Newer-generation antihistamines are less effective for non-allergic causes 1, 3

Chronic Sinusitis

• Minimum 3 weeks of antibiotics effective against H. influenzae, mouth anaerobes, and S. pneumoniae 3
• 3 weeks of oral antihistamine/decongestant 3
• 5 days of nasal decongestant followed by 3 months of intranasal corticosteroids 3

Adjunctive Therapy

Nasal saline irrigation improves symptoms through mechanical removal of mucus, enhanced ciliary activity, and disruption of inflammatory mediators. 1 Irrigation is more effective than saline spray because it better expels secretions. 1

Monitoring and Side Effects

Common Side Effects

• Dry mouth and transient dizziness from first-generation antihistamines 1
• Decongestants can cause insomnia, irritability, palpitations, and hypertension 1, 3

Serious Side Effects to Monitor

• Insomnia, urinary retention, jitteriness, tachycardia 1
• Worsening hypertension - monitor blood pressure after initiating decongestant therapy 1
• Increased intraocular pressure in glaucoma patients 1

Sequential Evaluation for Persistent Symptoms

If symptoms persist despite adequate upper airway treatment for 2 weeks, proceed with sequential evaluation for: 1

1. Asthma/non-asthmatic eosinophilic bronchitis - consider bronchial provocation testing if spirometry is normal 1
2. Gastroesophageal reflux disease (GERD) - initiate empiric therapy with proton pump inhibitor (omeprazole 20-40 mg twice daily before meals) for at least 8 weeks plus dietary modifications 1

Maintain all partially effective treatments rather than discontinuing them prematurely, as UACS, asthma, and GERD together account for approximately 90% of chronic cough cases. 1

Critical Pitfalls to Avoid

• Never use topical nasal decongestants (oxymetazoline, xylometazoline) for more than 3-5 consecutive days due to risk of rhinitis medicamentosa (rebound congestion). 1, 3
• Do not assume absence of typical symptoms rules out post nasal drip - approximately 20% have "silent" presentation. 1, 3
• Newer-generation antihistamines were found ineffective for acute cough in postviral upper respiratory infection. 1
• Post nasal drip can be confused with GERD due to overlapping symptoms. 1, 3
• For chronic cases, treatment duration of at least 3 weeks is recommended, with some conditions requiring 3 months of intranasal corticosteroids. 3