What is the best treatment approach for an adult with lingering nasal drainage, cough, and watery eyes, assuming no severe allergies or chronic conditions like asthma or chronic obstructive pulmonary disease (COPD)?

Treatment of Lingering Nasal Drainage, Cough, and Watery Eyes in Adults

Start immediately with a first-generation antihistamine/decongestant combination (such as chlorpheniramine with sustained-release pseudoephedrine or dexbrompheniramine with pseudoephedrine) as this is the most effective evidence-based treatment for upper airway cough syndrome with postnasal drip, which is the most common cause of these symptoms. 1

Initial Treatment Algorithm

First-Line Therapy (Days 1-14)

• Prescribe a first-generation antihistamine/decongestant combination as the cornerstone of treatment, with specific effective combinations including dexbrompheniramine maleate plus sustained-release pseudoephedrine sulfate, or azatadine maleate plus sustained-release pseudoephedrine sulfate. 1

• The older-generation antihistamines are superior to newer non-sedating antihistamines due to their anticholinergic drying properties, which directly address the nasal drainage and watery eyes. 1

• To minimize sedation, start with once-daily dosing at bedtime for a few days before increasing to twice-daily therapy. 1

• Most patients will see improvement within days to 2 weeks of initiating therapy. 1

• Common side effects include dry mouth and transient dizziness, but monitor for more serious effects including insomnia, urinary retention, jitteriness, tachycardia, worsening hypertension, and increased intraocular pressure in glaucoma patients. 1

Adjunctive Supportive Measures

• Add nasal saline irrigation (high-volume, 150 mL per nostril) which improves symptoms through mechanical removal of mucus, enhanced ciliary activity, and disruption of inflammatory mediators—this is more effective than saline spray because irrigation better expels secretions. 1

• For symptomatic cough relief, consider dextromethorphan as an over-the-counter cough suppressant, which is FDA-approved and may be the most effective non-prescription option. 2, 3

• Recommend adequate hydration, warm facial packs, steamy showers, and sleeping with the head of bed elevated as supportive care. 4

If No Improvement After 1-2 Weeks

Add Intranasal Corticosteroids

• Add intranasal corticosteroids such as fluticasone 100-200 mcg daily for a 1-month trial alongside the antihistamine/decongestant combination, as a single randomized controlled trial showed intranasal steroids given for 2 weeks are effective in allergic rhinitis-related cough. 1

• Intranasal corticosteroids are the most effective monotherapy for allergic rhinitis and are also effective for some forms of non-allergic rhinitis. 1

Alternative for Patients with Contraindications to Decongestants

• If the patient has hypertension, cardiovascular disease, or other contraindications to oral decongestants, use ipratropium bromide nasal spray (42 mcg per spray, 2 sprays per nostril 4 times daily) as an alternative, which provides anticholinergic drying effects without systemic cardiovascular side effects. 1

If Symptoms Persist Beyond 2-3 Weeks

Sequential Evaluation for Other Causes

• If symptoms persist despite adequate upper airway treatment for 2 weeks, proceed with sequential evaluation for other common causes of chronic cough, specifically asthma/non-asthmatic eosinophilic bronchitis and gastroesophageal reflux disease (GERD). 1, 4

• Maintain all partially effective treatments rather than discontinuing them prematurely, as upper airway cough syndrome, asthma, and GERD together account for approximately 90% of chronic cough cases in nonsmokers with normal chest radiographs. 1

Consider Post-Infectious Cough (If Recent Viral Illness)

• If the symptoms began following a viral upper respiratory infection and have persisted for 3-8 weeks, this represents post-infectious cough, which is managed differently. 4

• For post-infectious cough, inhaled ipratropium bromide 2-3 puffs four times daily has the strongest evidence for attenuating symptoms, with response expected within 1-2 weeks. 4

• Antibiotics are explicitly contraindicated for post-infectious cough unless there is clear evidence of bacterial sinusitis or early pertussis infection. 4

Critical Pitfalls to Avoid

• Never use topical nasal decongestants (oxymetazoline, xylometazoline) for more than 3-5 consecutive days due to the risk of rhinitis medicamentosa (rebound congestion). 1

• Newer-generation antihistamines (cetirizine, loratadine, fexofenadine) are less effective for non-allergic causes of postnasal drip cough compared to first-generation antihistamines. 1

• Approximately 20% of patients have "silent" postnasal drip with no obvious symptoms of drainage yet still respond to treatment, so don't exclude this diagnosis based on absence of subjective postnasal drip sensation alone. 1

• Monitor blood pressure after initiating decongestant therapy, as decongestants can worsen hypertension and cause tachycardia. 1

Red Flags Requiring Further Evaluation

• Return immediately if fever develops, hemoptysis occurs, or symptoms worsen. 4

• If cough persists beyond 8 weeks, obtain a chest X-ray and reclassify as chronic cough requiring systematic evaluation for upper airway cough syndrome, asthma, and GERD. 4

• Consider sinus imaging if persistent nasal symptoms despite topical therapy, particularly if air-fluid levels are present indicating acute bacterial sinusitis requiring antibiotics. 1