What are the likely etiologies of pharyngeal pruritus and a non‑productive cough lasting a few days, and what is the recommended management?

Throat Itching and Dry Cough of Few Days Duration

This is most likely an acute viral upper respiratory tract infection (URTI), and management should focus on symptomatic relief with dextromethorphan (60 mg for maximum effect) or menthol inhalation, as the condition is typically self-limiting and resolves within 2 weeks. 1

Likely Etiology

The combination of pharyngeal pruritus (throat itching) and non-productive cough lasting a few days strongly suggests:

• Viral URTI - This is the most common cause of acute cough (defined as lasting <3 weeks), present in 40-50% of URTI cases 1
• The throat itching represents upper airway irritation from the viral infection
• This is a benign, self-limiting condition in the absence of significant comorbidities 1

Management Approach

Immediate Assessment

First, determine the duration precisely:

• If <3 weeks: Treat as acute cough
• If 3-8 weeks: Consider post-infectious cough
• If >8 weeks: Evaluate as chronic cough with different diagnostic algorithm 1

Symptomatic Treatment for Acute Cough

For cough suppression, the evidence supports:

1. Dextromethorphan - The most effective non-sedating option

   • Standard over-the-counter doses are likely subtherapeutic
   • Maximum cough reflex suppression occurs at 60 mg with prolonged effect 1
   • Caution: Check combined preparations for other ingredients like paracetamol before recommending higher doses

2. Menthol inhalation - Can be prescribed as menthol crystals or proprietary capsules

   • Suppresses cough reflex acutely but effect is short-lived 1

3. Sedative antihistamines (first-generation)

   • Suppress cough but cause drowsiness
   • May be suitable specifically for nocturnal cough 1

4. Avoid codeine or pholcodine - These have no greater efficacy than dextromethorphan but carry a significantly worse adverse effect profile 1

For Upper Airway Symptoms

If prominent nasal stuffiness or post-nasal drip accompanies the throat itching:

• First-generation antihistamine plus decongestant has been shown in double-blind placebo-controlled studies to decrease cough severity and hasten resolution 2

What NOT to Do

• Do not prescribe antibiotics - The cause is viral, not bacterial 3
• Simple drinks and linctuses have variable efficacy with limited evidence 1

Red Flags Requiring Different Approach

Watch for features suggesting alternative diagnoses:

• Paroxysmal cough with post-tussive vomiting or inspiratory whoop → Consider Bordetella pertussis (whooping cough), which requires macrolide antibiotics if diagnosed early 3
• Cough persisting >3 weeks → Becomes post-infectious cough; consider trial of inhaled ipratropium 3
• Cough persisting >8 weeks → Requires full chronic cough evaluation including chest X-ray, spirometry, and assessment for upper airway cough syndrome, asthma, or gastroesophageal reflux 1

Expected Timeline

• Most acute URTI-associated coughs resolve within 2 weeks 1
• If using dextromethorphan, resolution should occur within days to 2 weeks
• If symptoms persist beyond 3 weeks, reassess for post-infectious causes or other etiologies

Common Pitfalls to Avoid

• Overprescribing antibiotics for viral illness
• Using subtherapeutic doses of dextromethorphan
• Missing pertussis in patients with characteristic paroxysmal cough
• Failing to reassess if cough persists beyond expected viral course