What are the recommended medications and dosages for treating a cough?

Recommended Cough Medications and Dosages

For acute viral cough, start with honey and lemon as first-line treatment; if pharmacological therapy is needed, use dextromethorphan 30-60 mg (not the standard OTC dose of 10-20 mg) for adults, as it provides superior safety compared to codeine while avoiding ineffective options like guaifenesin or standard antihistamines. 1, 2

First-Line Approach by Cough Type

Acute Viral Cough (Upper Respiratory Infection)

• Non-pharmacological first: Honey and lemon mixtures are as effective as many medications and should be tried initially 1, 2
• Dextromethorphan dosing: 30-60 mg provides optimal cough suppression in adults—standard OTC dosing (10-20 mg per FDA labeling) is subtherapeutic 1, 3
• Caution: Some dextromethorphan preparations contain acetaminophen or other ingredients; verify total daily dose to avoid toxicity 1, 2
• Menthol inhalation: Provides acute but short-lived relief when rapid symptom control is needed 1, 2
• Nocturnal cough: First-generation sedating antihistamines (like chlorpheniramine) are appropriate specifically for nighttime cough disrupting sleep 1, 2

Chronic Bronchitis

• Peripheral cough suppressants: Levodropropizine and moguisteine are recommended for short-term symptomatic relief (Grade A recommendation) 4
• Central suppressants: Codeine and dextromethorphan are recommended for short-term use (Grade B recommendation) 4
• Ipratropium bromide inhaled: The only inhaled anticholinergic recommended for cough suppression in chronic bronchitis (Grade A recommendation) 4
• Hypertonic saline and erdosteine: Recommended short-term to increase cough clearance (Grade A recommendation) 4

Postinfectious Cough

• First try: Inhaled ipratropium before central antitussives 1
• Severe paroxysms: Consider prednisone 30-40 mg daily for a short period 1
• Central antitussives: Use dextromethorphan only when other measures fail 1

What NOT to Use

Ineffective for Acute Viral Cough (URI)

• Codeine: No greater efficacy than dextromethorphan but significantly more adverse effects (drowsiness, nausea, constipation, physical dependence)—Grade D recommendation against use 4, 1, 2
• Guaifenesin (expectorant): Despite FDA approval, evidence shows inconsistent benefit; not recommended for acute cough 4, 5, 6
• Standard antihistamines alone: Not effective for cough suppression in URI (Grade D recommendation) 4, 7
• Albuterol: Not recommended for cough not due to asthma (Grade D recommendation) 4
• Zinc preparations: Not recommended for acute cough due to common cold (Grade D recommendation) 4
• OTC combination cold medications: Not recommended except older antihistamine-decongestant combinations (Grade D recommendation) 4

Special Populations

• Children under 4 years: Do not use dextromethorphan per FDA labeling 3
• Children generally: Antitussives, antihistamines, and decongestants show no benefit over placebo 7
• Children with cough: Honey may provide modest benefit and is preferred over medications 6, 7

Practical Dosing Algorithm

Adults (≥12 years)

• Dextromethorphan: 30-60 mg every 12 hours (maximum 60 mg per dose, 120 mg per 24 hours for optimal effect—note this exceeds standard FDA labeling of 10-20 mL/20-40 mg per 12 hours) 1, 3
• Ipratropium inhaled (for chronic bronchitis): Standard metered-dose inhaler dosing 4
• Prednisone (severe postinfectious cough): 30-40 mg daily for short course 1

Children (when appropriate)

• Ages 6-12 years: Dextromethorphan 5 mL (15 mg) every 12 hours per FDA labeling, maximum 10 mL (30 mg) in 24 hours 3
• Ages 4-6 years: Dextromethorphan 2.5 mL (7.5 mg) every 12 hours, maximum 5 mL (15 mg) in 24 hours 3
• Honey: Preferred over medications for symptomatic relief 6, 7

Critical Pitfalls to Avoid

• Using subtherapeutic dextromethorphan doses: Standard OTC dosing often provides inadequate cough suppression; 60 mg is the dose for maximum reflex suppression 1
• Prescribing codeine: No efficacy advantage over dextromethorphan with substantially worse side effect profile 4, 1, 2
• Using expectorants for dry cough: Guaifenesin lacks consistent evidence for acute cough despite widespread use 4, 5, 6
• Combining multiple OTC products: Risk of duplicating active ingredients, especially acetaminophen toxicity 1, 2
• Missing serious causes: Always assess for increasing breathlessness (asthma/anaphylaxis), fever with purulent sputum (pneumonia), hemoptysis, or foreign body before treating symptomatically 2