A 2-year-old with a barky cough and mild stridor is treated with a single dose of which medication that has strong evidence for efficacy?

• A. Nebulized hypertonic saline.
• B. Epinephrine inhalation.
• C. Dexamethasone.
• D. Oral antibiotics.

Answer: (C)

In viral croup, reducing the subglottic airway edema with an anti-inflammatory is the most effective approach, and a single dose of dexamethasone does this well. Its anti-inflammatory effect is long-lasting, so one dose can significantly lessen stridor and respiratory distress for about 24 hours and often shortens the course without needing additional treatment. For a mild case with a barky cough and mild stridor, this single-dose corticosteroid is strongly supported by evidence as the best initial treatment.

Nebulized hypertonic saline hasn’t shown consistent benefit for typical croup and isn’t a first-line choice. Epinephrine inhalation can provide rapid, short-term relief in more moderate to severe croup, but it is usually used in combination with steroids for those cases, and its effect wears off quickly. Oral antibiotics are not indicated because croup is viral, and antibiotics don’t improve viral croup symptoms.