How to manage an elderly patient with asthma and a persistent cough that doesn't improve with over-the-counter (OTC) treatments, such as citrate (citric acid) and paracetamol (acetaminophen) and dry cough syrup?

Management of Persistent Cough in an Elderly Asthmatic Patient

In an elderly asthmatic patient with persistent dry cough unresponsive to over-the-counter symptomatic treatments, you must immediately optimize asthma controller therapy with inhaled corticosteroids (ICS) as the cornerstone, while systematically evaluating for the three most common causes of chronic cough: upper airway cough syndrome (UACS), poorly controlled asthma, and gastroesophageal reflux disease (GERD). 1, 2

Immediate Assessment and Red Flags

First, assess whether this represents worsening asthma control or an acute exacerbation requiring urgent intervention:

• Check for severe asthma features: inability to complete sentences, respiratory rate >25/min, heart rate >110/min, peak expiratory flow (PEF) <50% predicted 1, 2
• Measure oxygen saturation: if <92% on room air or PEF <33% predicted after bronchodilator, immediate hospital referral is mandatory 2
• Perform spirometry or peak flow measurement: this is essential in elderly patients where symptoms alone are unreliable 3, 4

Optimize Asthma Controller Therapy First

The patient's persistent cough likely reflects inadequately controlled asthma, which is extremely common in elderly patients who are often undertreated 5, 3, 6:

• Initiate or increase inhaled corticosteroids immediately: Start with fluticasone 100-250 mcg/day (or equivalent) if not already on ICS, or double the current dose if already prescribed 1, 2
• Continue short-acting beta-agonists (SABA) for symptom relief: but monitor frequency of use—needing SABA >2 days/week indicates poor control requiring step-up therapy 1
• Allow 4-8 weeks for full response: while some improvement may occur within 1 week, complete cough resolution with ICS can take up to 8 weeks 1

Critical pitfall: The British Thoracic Society explicitly states that antibiotics should only be given if bacterial infection is documented, and cough suppressants/symptomatic treatments (like the "dry cough syrup" mentioned) are unhelpful for asthma-related cough 1, 2

Systematic Evaluation for Chronic Cough Causes

If cough persists despite optimized ICS therapy for 4-8 weeks, evaluate sequentially for the three most common causes 1:

1. Upper Airway Cough Syndrome (UACS/Post-Nasal Drip)

• Look for: nasal congestion, post-nasal drip sensation, throat clearing, cobblestone appearance of posterior pharynx 1
• Trial treatment: intranasal corticosteroid (fluticasone 2 sprays each nostril daily) plus oral antihistamine for 2-4 weeks 1, 7

2. Poorly Controlled Asthma Despite ICS

• Perform bronchoprovocation testing (methacholine challenge) if available—negative predictive value approaches 100% for ruling out asthma 1, 3, 4
• If spirometry shows obstruction with <15% reversibility, this doesn't exclude asthma in elderly patients; consider a trial of oral corticosteroids (prednisolone 30-40 mg daily for 5-10 days) to definitively assess response 1, 8, 3
• Add long-acting beta-agonist (LABA) only if already on ICS and symptoms persist—never use LABA as monotherapy due to increased mortality risk 1, 2, 9

3. Gastroesophageal Reflux Disease (GERD)

• Consider empiric trial if cough persists after treating UACS and optimizing asthma: proton pump inhibitor (PPI) plus dietary/lifestyle modifications for 8-12 weeks 1
• GERD-induced cough may lack typical heartburn symptoms in elderly patients 1

Special Considerations in Elderly Asthmatics

Exercise extreme caution with beta-agonists in elderly patients: Meta-analyses show increased cardiovascular mortality and morbidity with both short- and long-acting beta-agonists, particularly in those with cardiovascular comorbidities 6

• Monitor cardiovascular status and serum potassium regularly if using beta-agonists 6
• Consider leukotriene receptor antagonists (montelukast) as alternative add-on therapy instead of LABA—fewer adverse effects and may be more appropriate in elderly patients with cardiac disease 1, 6

Check inhaler technique at every visit: Poor technique is extremely common in elderly patients and leads to treatment failure 1, 6

Screen for comorbidities that worsen cough: heart failure, GERD, ACE inhibitor use, chronic aspiration, and vocal cord dysfunction are all more common in elderly patients 1, 4

When to Refer

Refer to respiratory specialist if: 1

• Cough persists despite sequential trials of treatment for UACS, asthma, and GERD
• Diagnostic uncertainty between asthma and COPD
• Requiring step 4 or higher therapy (high-dose ICS plus LABA)
• Recurrent exacerbations requiring oral corticosteroids

Monitoring and Follow-up

• Schedule follow-up within 1 week after initiating or changing therapy to assess response objectively with spirometry or peak flow 1, 2
• Provide written asthma action plan with specific instructions for recognizing worsening symptoms and when to increase treatment 1, 2
• Measure peak flow or spirometry at each visit: subjective symptom assessment is unreliable in elderly patients who have poor perception of bronchoconstriction 6, 4