What are the recommended treatments for a cough in a healthy adult, including antihistamines and cough syrups?

Treatment Recommendations for Acute Cough in Healthy Adults

For a healthy adult with acute cough, start with honey and lemon as a simple home remedy, which is as effective as most pharmacological treatments; if additional relief is needed, use dextromethorphan 60 mg (not the standard lower OTC dose) for optimal cough suppression, or first-generation sedating antihistamines specifically for nighttime cough. 1, 2

First-Line Approach: Non-Pharmacological Treatment

• Honey and lemon mixtures should be your initial recommendation as they provide symptomatic relief comparable to over-the-counter medications without side effects 1, 2
• Simple voluntary cough suppression techniques may be sufficient to reduce cough frequency through central modulation of the cough reflex 1, 2

Second-Line: Pharmacological Options When Needed

Dextromethorphan (Preferred Antitussive)

• Dextromethorphan is the recommended antitussive due to superior safety profile compared to codeine-based products 1, 2
• The standard OTC dosing is subtherapeutic; maximum cough reflex suppression occurs at 60 mg, which can provide prolonged relief 1, 2
• Dextromethorphan is FDA-approved to temporarily relieve cough due to minor throat and bronchial irritation from common cold 3
• Common pitfall: Most OTC preparations contain inadequate doses (typically 15-30 mg), which explains inconsistent patient responses 2
• Exercise caution with higher doses as some combination products contain paracetamol or other ingredients that could lead to unintended overdose 1, 2

Antihistamines (For Nocturnal Cough)

• First-generation sedating antihistamines suppress cough but cause drowsiness, making them particularly suitable when cough disrupts sleep 1, 2
• Second-generation non-sedating antihistamines show conflicting evidence and are not reliably effective for cough 1
• Important distinction: The sedative properties, not the antihistamine effect itself, appear responsible for cough suppression 1

Menthol Inhalation (For Quick Temporary Relief)

• Menthol by inhalation suppresses the cough reflex acutely but provides only short-lived relief 1, 2
• Can be prescribed as menthol crystals or proprietary capsules for immediate symptom control 1

What NOT to Recommend

Avoid Codeine and Pholcodine

• Codeine and pholcodine have no greater efficacy than dextromethorphan but carry significantly higher adverse effect profiles including drowsiness, nausea, constipation, and risk of physical dependence 1, 2
• Opiate antitussives are specifically not recommended for acute viral cough 1

Limited Evidence for Other Options

• Guaifenesin (expectorant) shows inconsistent results across studies, with some showing benefit and others showing no difference from placebo 4, 5
• Antihistamine-decongestant combinations show conflicting evidence in adults, though some studies favor active treatment 4, 5
• In children specifically, antihistamines, decongestants, and their combinations do not relieve cough better than placebo 5, 6

Clinical Algorithm for Acute Cough Management

1. Confirm benign viral etiology: Rule out pneumonia (check for fever, dyspnea, abnormal lung exam) or other serious causes requiring specific treatment 1

2. Start with honey and lemon for all patients as first-line symptomatic treatment 1, 2

3. If additional relief needed during daytime: Dextromethorphan 60 mg (higher than typical OTC dosing) 1, 2

4. If cough disrupts sleep: First-generation sedating antihistamine at bedtime 1, 2

5. For immediate but brief relief: Menthol inhalation 1, 2

6. Avoid codeine-containing products due to poor benefit-to-risk ratio 1, 2

Important Caveats

• Acute viral cough is almost invariably benign and self-limited; prescribed treatment can be regarded as unnecessary from a medical standpoint, though it may reduce patient distress 1
• There is little evidence of specific pharmacological effects for most OTC cough preparations; patient-reported benefits may reflect placebo effects or the soothing properties of liquid preparations 1
• The evidence base for OTC cough medications is limited by small study numbers, conflicting results, and unclear clinical significance of positive findings 4, 5
• Do not use antitussives for productive cough where clearance of secretions is beneficial 2