Croup is a common paediatric respiratory illness involving inflammation and narrowing of the subglottic region of the larynx, frequently precipitated by viral infections. Treatment is aimed at decreasing symptoms and reducing inflammation. Glucocorticoids are effective by oral, parenteral or nebulized routes, and continue to provide the mainstay of therapy. The common oral dexamethasone dose (0.6 mg/kg) may exceed the dose required for good clinical efficacy. Nebulized epinephrine provides effective additional therapy for more severe cases. L-epinephrine appears to be comparable to racemic epinephrine, although further study is warranted. Limited data suggest that heliox is also effective in the short-term management of refractory croup. The use of humidified oxygen remains controversial, as good data are lacking.