Anidulafungin is an echinocandin antifungal used to treat invasive fungal infections caused by Candida or Aspergillus species. While the echinocandins are generally well tolerated, novel adverse reactions may occur. Specifically, echinocandins have been associated with histamine-mediated infusion reactions. We describe a novel case of flash pulmonary oedema associated with anidulafungin administration, which may be related to histamine release.A 52-year-old male developed flash pulmonary oedema after the first dose of anidulafungin, which was characterized by acute onset of spasmodic cough with shortness of breath and chest tightness with subsequent new bilateral perihilar and interstitial oedema visualized on chest X-ray. The patient was treated appropriately with diphenhydramine, hydrocortisone and albuterol with complete recovery and a normal follow-up chest X-ray the following day.This is the first report of pulmonary oedema attributable to an echinocandin antifungal agent. While such infusion-related adverse events including pulmonary oedema appear uncommon, it is important for clinicians to be aware of this possibility and maintain the drug's infusion rate to <1·1 mg/min and monitor for signs and symptoms of pulmonary oedema.