Case Report Open Access 15 Methaemoglobinaemia is a rare but potentially life -threatening cause of hypoxemia that may be overlooked in emergency settings. We report a case of acquired methaemoglobinaemia in a 36 - year-old man following inhalation of an alkyl nitrite –containing recreational product (“Super Rush ”). The patient presented with cyanosis and hypoxemia on pulse oximetry despite minimal symptoms and preserved arterial oxygen tension. Diagnosis was confirmed by co -oximetry demonstrating elevated methaemoglobin levels. Prompt treatment with intravenous methylene blue led to rapid clinical and biochemical improvement. This case highlights the importance of suspecting and recognising recreational inhalants as a cause of methaemoglobinaemia and the utility of co -oximetry in patients with unexplained cyanosis and a saturation gap

Case Report Open Access 15 Methaemoglobinaemia is a rare but potentially life -threatening cause of hypoxemia that may be overlooked in emergency settings. We report a case of acquired methaemoglobinaemia in a 36 - year-old man following inhalation of an alkyl nitrite –containing recreational product (“Super Rush ”). The patient presented with cyanosis and hypoxemia on pulse oximetry despite minimal symptoms and preserved arterial oxygen tension. Diagnosis was confirmed by co -oximetry demonstrating elevated methaemoglobin levels. Prompt treatment with intravenous methylene blue led to rapid clinical and biochemical improvement. This case highlights the importance of suspecting and recognising recreational inhalants as a cause of methaemoglobinaemia and the utility of co -oximetry in patients with unexplained cyanosis and a saturation gap