What are the treatment options for cough?

Treatment of Cough

A systematic approach to cough treatment begins with identifying the underlying cause through comprehensive assessment, followed by targeted therapy for the specific etiology, as this is far more effective than nonspecific cough suppressants. 1

Initial Diagnostic Steps

• Classify the cough duration: acute (<3 weeks), subacute (3-8 weeks), or chronic (>8 weeks), as this guides the entire management strategy 1, 2
• Obtain a chest radiograph to exclude pneumonia, malignancy, pulmonary embolism, and other serious pathology 3, 1, 2
• Discontinue ACE inhibitors immediately if the patient is taking them, as these commonly cause persistent dry cough that resolves with cessation 1, 2
• Advise smoking cessation for all smokers, as cough typically resolves within 4 weeks of quitting 1, 2
• Perform spirometry to identify airway obstruction or asthma 2

Treatment Algorithm for Chronic Cough

Step 1: Upper Airway Cough Syndrome (UACS)

• Start with first-generation antihistamine/decongestant combination as initial empiric therapy 1, 2
• This addresses postnasal drip, rhinosinusitis, and allergic rhinitis as common causes 1

Step 2: Asthma and Nonasthmatic Eosinophilic Bronchitis (NAEB)

• For suspected asthma: initiate inhaled corticosteroids combined with long-acting β-agonists 1
• For NAEB: inhaled corticosteroids alone are first-line treatment 1
• Consider a trial of oral prednisone 30-40 mg daily for severe cases when other causes are excluded 2
• Both conditions show eosinophilic airway inflammation and respond well to corticosteroids 4

Step 3: Gastroesophageal Reflux Disease (GERD)

• Initiate proton pump inhibitors (PPIs) if cough persists after addressing UACS and asthma 1, 2
• Add prokinetic therapy if there is minimal response to PPI therapy alone 1

Symptomatic Treatment for Nonproductive Cough

First-Line Antitussives

• Dextromethorphan is the preferred first-line antitussive due to substantial benefit and favorable safety profile compared to other agents 5
• Maximum cough suppression occurs at 60 mg with prolonged effect 5
• FDA-approved for temporary relief of cough due to minor throat and bronchial irritation from common cold or inhaled irritants 6
• More effective than codeine with fewer side effects 5

Alternative Symptomatic Options

• Honey and lemon mixtures provide effective symptomatic relief as a home remedy 1, 5
• First-generation antihistamines with sedative properties are particularly helpful for nocturnal cough 5
• Menthol lozenges or inhalation provide short-term suppression through cold and menthol-sensitive receptors 5
• Adequate hydration should be encouraged for symptom management 5

Second-Line Antitussives

• Codeine may be used for short-term relief but has limited efficacy for upper respiratory infections and carries risks of respiratory depression, drowsiness, and physical dependence 5
• Benzonatate can be considered for opioid-resistant cough when other options fail 5
• Low-dose morphine has shown benefit for idiopathic chronic cough refractory to other treatments 3

Specific Populations

• Lung cancer patients: centrally acting cough suppressants such as dihydrocodeine and hydrocodone are recommended, with median effective dose of 10 mg/d hydrocodone 3
• Pediatric patients: use pediatric-specific protocols; honey may be considered for children over 1 year of age 1

Management of Refractory Chronic Cough

When cough persists despite sequential trials of therapy:

• Multimodality speech pathology therapy including cough suppression techniques, vocal hygiene training, and psychoeducational counseling shows promising results (88% improvement vs 14% in controls) 3, 2
• Gabapentin trial can be considered for refractory chronic cough 2
• Low-dose opiates for symptom control when all alternatives have failed, particularly in palliative care 2
• Referral to specialist (pulmonologist or otolaryngologist) when diagnosis remains unclear or cough severely impacts quality of life 2

Special Considerations for Specific Conditions

Lung Cancer-Associated Cough

• Comprehensive assessment first to identify treatable causes including pleural effusion, infection, COPD exacerbation, GERD, lymphangitic carcinomatosis, or treatment-induced cough 3
• Endobronchial brachytherapy may improve cough in selected patients with endobronchial tumors 3
• Cough suppression exercises as alternative or additional to pharmacological therapy where available (Grade 2C) 3

Aspiration and Dysphagia

• Videofluoroscopic swallow evaluation or fiberoptic endoscopic evaluation to identify appropriate treatment 2
• Management by organized multidisciplinary teams 2
• Surgical intervention may be considered for intractable aspiration 2

Idiopathic Chronic Cough

• Predominantly affects middle-aged women, often starting around menopause 3
• Shows lymphocytic airway inflammation and heightened cough reflex 3
• Treatment options include dextromethorphan, baclofen, nebulized local anesthetics (lidocaine, mepivicaine), or low-dose morphine 3

What NOT to Do

• Do not prescribe antibiotics for nonproductive cough due to viral infections, even when phlegm is present 5
• Do not use expectorants, mucolytics, or bronchodilators for acute nonproductive cough 5
• Do not use zinc preparations for acute cough due to common cold 5
• Do not suppress cough in conditions where clearance is important (pneumonia, bronchiectasis) 3
• Do not rely solely on cough characteristics for diagnosis, as they have limited diagnostic value 1, 2
• Do not treat only one potential cause, as multiple factors often contribute to chronic cough 1, 2

Critical Warnings and Precautions

Dextromethorphan Warnings

• Do not use with MAOIs or within 2 weeks of stopping MAOI therapy 6
• Contains sodium metabisulfite, which may cause allergic-type reactions 6
• Stop use if cough lasts more than 7 days, returns, or occurs with fever, rash, or persistent headache 6
• Do not use for chronic cough from smoking, asthma, or emphysema, or when cough produces excessive mucus 6

Red Flags Requiring Immediate Medical Attention

• Coughing up blood (hemoptysis) 5
• Breathlessness 5
• Prolonged fever with systemic illness 5
• Underlying COPD, heart disease, diabetes, or asthma with worsening symptoms 5
• Recent hospitalization 5
• Symptoms persisting beyond 3 weeks without improvement 5

Common Pitfalls to Avoid

• Avoid prolonged empiric treatment without reassessment, as this delays diagnosis of serious underlying conditions 2
• Do not prescribe antibiotics for postinfectious cough unless there is clear evidence of bacterial infection 2
• Exercise caution with higher doses of dextromethorphan, as some preparations contain additional ingredients like acetaminophen 5
• Recognize that cough in interstitial lung diseases may be due to other etiologies rather than the disease itself 3