A 27-year-old woman was admitted to a large teaching hospital with a 3-day history of increasing breathlessness, wheeze, and nonproductive cough. She was known to have asthma, which was managed by her family physician with budesonide 200 μg/formoterol 6 μg Turbuhaler (AstraZeneca, PLC; London, England) two inhalations twice daily and terbutaline 500 μg Turbuhaler as required.She admitted to poor compliance with her medication and had only started retaking her treatment in the week prior to admission. In the previous 5 years, she had two hospital admissions for mild exacerbations of asthma, both of which had settled within 2 days. She had received no further courses of corticosteroids. She was otherwise healthy with no history of diabetes mellitus or alcohol excess. She had a 3 pack-year smoking history, having stopped smoking 6 months prior to admission.