What is the first‑line over‑the‑counter therapy for a healthy adult with an acute mildly productive cough?

First-Line OTC Therapy for Acute Mildly Productive Cough

For a healthy adult with acute mildly productive cough, start with honey and lemon as first-line therapy, followed by guaifenesin (an expectorant) if additional relief is needed, reserving dextromethorphan only for severe non-productive cough that disrupts sleep or quality of life. 1, 2, 3

Initial Non-Pharmacological Approach

• Honey and lemon mixtures are the simplest, cheapest, and often most effective first-line treatment for acute viral cough, with evidence of patient-reported benefit comparable to pharmacological agents 1, 2
• The mechanism appears to be central modulation of the cough reflex, where voluntary suppression combined with the demulcent effect of honey coating the pharynx reduces cough frequency 1
• Acute cough associated with viral upper respiratory tract infection is typically benign and self-limiting, lasting 1-3 weeks without requiring prescribed medication 4, 2

Pharmacological Options for Productive Cough

Expectorants (Preferred for Productive Cough)

• Guaifenesin is the appropriate OTC medication for mildly productive cough, as it helps loosen phlegm and thin bronchial secretions to make coughs more productive 3
• This is critical because productive cough serves a protective clearance function, and suppressing it may be counterproductive 2

Antitussives (Use Cautiously)

• Dextromethorphan should NOT be first-line for productive cough because central cough suppressants interfere with necessary mucus clearance 1, 2
• If the cough becomes predominantly dry and disruptive (especially at night), dextromethorphan 30-60 mg can be considered, as standard OTC doses (15-30 mg) are often subtherapeutic 1, 2
• Dextromethorphan has superior safety compared to codeine-based products, which should be avoided due to adverse effects (drowsiness, constipation, dependence) without additional efficacy 1, 2

Adjunctive Options

• First-generation sedating antihistamines (like diphenhydramine) are particularly useful for nocturnal cough disrupting sleep, though they cause drowsiness 1, 2
• Menthol inhalation provides acute but short-lived cough suppression and can be used for quick temporary relief 1, 2

Clinical Algorithm

1. Start with honey and lemon for all acute mildly productive cough 1, 2
2. Add guaifenesin if patient desires additional symptomatic relief to help clear secretions 3
3. Consider dextromethorphan 30-60 mg only if cough becomes predominantly dry and severely disrupts sleep or quality of life 1, 2
4. Use sedating antihistamines specifically for nighttime cough preventing sleep 1, 2

Critical Red Flags Requiring Medical Evaluation

• Hemoptysis (any amount of blood in sputum) 4, 2
• Prominent systemic illness with fever, malaise, or purulent sputum suggesting bacterial infection 4, 2
• Increasing breathlessness suggesting asthma, anaphylaxis, or pneumonia 2
• Cough persisting beyond 3 weeks requires full diagnostic workup rather than continued symptomatic treatment 4, 1

Common Pitfalls to Avoid

• Do not suppress productive cough with antitussives when clearance of secretions is beneficial 1, 2
• Avoid codeine-containing products which have no efficacy advantage over dextromethorphan but significantly more adverse effects 1, 2
• Do not use subtherapeutic doses of dextromethorphan (less than 30 mg) if choosing this agent, as they provide inadequate relief 1, 2
• Check combination products carefully to avoid excessive acetaminophen or other ingredients when using higher dextromethorphan doses 1
• Antibiotics have no role in acute viral cough and should not be used due to resistance concerns 5