What over‑the‑counter medications and dosing are appropriate for a typical adult with a self‑limited viral cough or cold, including safety considerations?

Over-the-Counter Medications for Cough and Cold in Adults

For adults with viral cough and cold, start with honey and lemon as first-line treatment; if pharmacological therapy is needed, use dextromethorphan 30-60 mg (not the subtherapeutic standard OTC dose) for dry cough, or consider combination antihistamine-decongestant products for multiple symptoms, while avoiding codeine-based products entirely. 1, 2

First-Line Non-Pharmacological Approach

• Simple home remedies like honey and lemon are as effective as many pharmacological treatments and should be tried first for benign viral cough 3, 1, 2
• Voluntary cough suppression through central modulation may be sufficient to reduce cough frequency in some patients 3, 1
• Adequate hydration and humidified air may provide symptomatic relief without adverse effects 4

Pharmacological Options for Dry Cough

Dextromethorphan (Preferred Agent)

• Dextromethorphan is the preferred antitussive due to superior safety profile compared to opioid alternatives 1, 2, 5
• Standard OTC dosing (10-15 mg) is often subtherapeutic; maximum cough suppression occurs at 60 mg 3, 1, 2
• Recommended dosing: 10-15 mg three to four times daily (every 6-8 hours), or 30-60 mg for more severe symptoms, with maximum daily dose of 120 mg 2, 5
• A bedtime dose of 15-30 mg may help suppress nighttime cough and promote sleep 2
• Critical pitfall: Many combination products contain acetaminophen or other ingredients—check labels carefully to avoid toxicity at higher dextromethorphan doses 3, 1, 2

Alternative Options for Specific Situations

• First-generation sedating antihistamines (e.g., diphenhydramine) are particularly useful for nocturnal cough when sleep disruption is the primary concern 3, 1, 2
• Menthol inhalation (menthol crystals or proprietary capsules) provides acute but short-lived cough suppression 3, 1
• Codeine and pholcodine should be avoided—they have no greater efficacy than dextromethorphan but significantly more adverse effects (drowsiness, nausea, constipation, physical dependence) 3, 1, 2, 5

Pharmacological Options for Nasal Symptoms

Decongestants

• Topical (intranasal) and oral decongestants relieve nasal congestion in adults 4
• Limit topical decongestants to 3 days maximum to avoid rebound congestion 4

Antihistamines

• Combination antihistamine-decongestant products provide modest symptom relief—1 in 4 patients experiences significant benefit 3
• Newer non-sedating antihistamines (e.g., cetirizine 10 mg once daily) are ineffective for cough but may help with rhinorrhea and sneezing 6, 4
• First-generation antihistamines alone (without decongestant) are not effective for cold symptoms unless cough suppression at night is needed 3, 7

Medications for Productive Cough

• Guaifenesin (expectorant) may help loosen mucus in productive cough, though evidence is mixed 8, 7
• Dosing: 200-400 mg every 4 hours, up to 6 times daily (immediate-release) or extended-release formulations every 12 hours 8
• Hypertonic saline and erdosteine may increase cough clearance on a short-term basis 5

What NOT to Use

• Antibiotics have no role in viral upper respiratory infections and cause more harm than benefit (number needed to harm = 8 for adverse effects) 3
• Codeine has not been shown to effectively treat cough from common cold 4, 9
• Central cough suppressants have limited efficacy for acute viral cough 5

Red Flags Requiring Medical Evaluation

• Seek immediate medical attention for: 3, 1
  • Hemoptysis (coughing up blood)
  • Significant breathlessness or tachypnea
  • High fever >39°C with purulent discharge for ≥3 consecutive days
  • Symptoms persisting >10-14 days or worsening after initial improvement
  • Suspected foreign body inhalation
  • Underlying serious illness (immunocompromised, significant comorbidities)

Practical Treatment Algorithm

1. Start with honey and lemon mixture for all patients with benign viral cough 3, 1, 2

2. For persistent dry cough during the day:

   • Add dextromethorphan 30-60 mg as needed (not standard 10-15 mg dose) 1, 2
   • Check combination products for other ingredients before dosing 3, 1

3. For nighttime cough disrupting sleep:

   • Use dextromethorphan 15-30 mg at bedtime 2
   • OR first-generation antihistamine (e.g., diphenhydramine) 3, 1

4. For multiple cold symptoms (congestion, rhinorrhea, cough):

   • Consider combination antihistamine-decongestant product 3, 4

5. For productive cough with chest congestion:

   • Consider guaifenesin 200-400 mg every 4-6 hours 8

6. Reassure patients that symptoms typically last up to 2 weeks and to follow up if symptoms worsen or persist beyond expected recovery time 3

Common Pitfalls to Avoid

• Using subtherapeutic doses of dextromethorphan (10-15 mg) that provide inadequate relief 3, 1
• Prescribing codeine-based products which offer no advantage but increased side effects 3, 1, 5
• Exceeding 3 days of topical decongestant use, leading to rebound congestion 4
• Overlooking acetaminophen or other ingredients in combination dextromethorphan products when using higher doses 3, 1, 2
• Prescribing antibiotics for viral symptoms—this increases antibiotic resistance without benefit 3