What is the initial treatment approach for a patient presenting with a cough, considering their age, medical history, and current medications, including conditions such as asthma (chronic obstructive airway disease) or Chronic Obstructive Pulmonary Disease (COPD)?

Initial Treatment Approach for Cough

Begin treatment by immediately classifying cough duration as acute (<3 weeks), subacute (3-8 weeks), or chronic (>8 weeks), as this determines your entire diagnostic and therapeutic pathway. 1, 2

Immediate Actions Before Starting Treatment

Critical Medication Review

• Stop ACE inhibitors immediately if the patient is taking one – this is a common reversible cause that resolves cough in most cases 1, 2
• Replace the ACE inhibitor with an alternative antihypertensive agent 3

Smoking Assessment

• If the patient smokes, counsel and assist with cessation as a priority – 90-94% of smokers experience cough resolution within the first year of quitting 2
• Chronic cough in active smokers requires smoking cessation before other interventions 3

Rule Out Life-Threatening Conditions

• Assess for pneumonia or pulmonary embolism by checking for tachypnea, tachycardia, dyspnea, fever >38.5°C, or abnormal lung findings 1
• Obtain a chest radiograph if any of these signs are present 1
• Evaluate for respiratory distress: markedly elevated respiratory rate, intercostal retractions, grunting, cyanosis, or altered mental status 1, 2

Treatment Algorithm Based on Cough Duration

Acute Cough (<3 weeks)

For common cold-related cough:

• Prescribe a first-generation antihistamine/decongestant combination (e.g., chlorpheniramine with pseudoephedrine) plus naproxen 1
• Do NOT use newer non-sedating antihistamines – they are ineffective for cough 1
• Consider honey for patients over 1 year of age 1
• Paracetamol for fever and associated symptoms 1

For acute exacerbation of COPD or chronic bronchitis:

• Administer a short course (10-15 days) of systemic corticosteroids 1
• Consider empiric antibiotic therapy if bacterial infection is suspected (high fever, purulent sputum) 1

Subacute Cough (3-8 weeks)

• Determine if this is post-infectious (following a respiratory infection) or non-infectious 3, 2
• For post-infectious cough, prescribe dextromethorphan 60 mg for maximum cough suppression (standard OTC doses are subtherapeutic) 4
• Consider ipratropium bromide inhaler, which has demonstrated efficacy in post-infectious cough 4, 5
• If cough persists beyond 3 weeks, mandatory reassessment is required – evaluate for pertussis, pneumonia, or progression to chronic causes 4

Chronic Cough (>8 weeks)

Use a sequential and additive treatment approach, as multiple causes frequently coexist: 3, 1, 2

Step 1: Treat Upper Airway Cough Syndrome (UACS)

• Start with an oral first-generation antihistamine/decongestant combination 3, 1, 2
• Add a topical nasal corticosteroid if prominent upper airway symptoms (nasal congestion, postnasal drip) are present 2
• Continue for 2-4 weeks before moving to next step 2

Step 2: Evaluate and Treat for Asthma

• Perform spirometry to assess for reversible airflow obstruction 2
• If spirometry shows reversibility, treat with inhaled corticosteroids plus inhaled bronchodilators 1, 2
• If spirometry is normal but asthma is still suspected, perform bronchoprovocation challenge testing 3, 2
• If bronchoprovocation testing is unavailable, give an empiric trial of inhaled corticosteroids and bronchodilators 3, 2
• For refractory cases, add a leukotriene receptor antagonist before escalating to oral corticosteroids 1

Step 3: Treat Non-Asthmatic Eosinophilic Bronchitis (NAEB)

• Perform induced sputum test for eosinophils if available 3, 2
• If testing is unavailable, give an empiric trial of inhaled corticosteroids 3, 2

Step 4: Treat Gastroesophageal Reflux Disease (GERD)

• Initiate empiric treatment with proton pump inhibitors if typical reflux symptoms are present 2
• This step is taken if cough persists after treating UACS and asthma 3

Step 5: Advanced Evaluation

• If cough persists after 4-6 weeks of empiric treatment for all common causes, pursue high-resolution CT scan or bronchoscopic evaluation 2
• Refer to a specialist cough clinic when diagnosis remains unclear 2

Special Considerations for Patients with Asthma or COPD

Asthma Patients

• Optimize controller therapy with inhaled corticosteroids and long-acting beta-agonists first 1, 2
• Assess for poor asthma control, environmental triggers, or medication non-adherence 3
• Consider adding leukotriene receptor antagonists for persistent cough despite optimized inhaled therapy 1

COPD Patients

• For acute exacerbations with cough, use systemic corticosteroids for 10-15 days 1
• Note that codeine has been shown ineffective for COPD-related cough in controlled trials 6, 7
• Ipratropium bromide may be more effective than opioid antitussives in this population 5

Symptomatic Antitussive Therapy

When specific treatment fails or for severe symptomatic relief:

• Dextromethorphan 60 mg provides maximum cough reflex suppression (standard OTC doses are subtherapeutic) 4
• Codeine or hydrocodone can be used but have more side effects and no greater efficacy than high-dose dextromethorphan 4, 7
• Reserve slow-release morphine only for the most severe chronic cough or terminal cancer patients 6, 7, 8
• Consider gabapentin, amitriptyline, or pregabalin for refractory chronic cough based on case reports 6, 7

Critical Pitfalls to Avoid

• Do NOT rely on cough characteristics alone for diagnosis – they have little diagnostic value 2
• Do NOT treat only one cause – multiple factors often contribute simultaneously, requiring additive sequential therapy 3, 1, 2
• Do NOT prescribe antibiotics for post-viral cough – they have absolutely no role except in suspected pertussis 4
• Do NOT use guaifenesin for chronic cough in asthma or COPD – it is only indicated for acute productive cough 9
• Do NOT continue antitussive therapy beyond 3 weeks without reassessment – persistent cough requires evaluation for underlying causes 4
• Do NOT use routine cough suppressants when cough clearance is important (e.g., pneumonia, bronchiectasis) 2