Early Recognition and Management of Severe Sodium Nitrite Intoxication: A Case Report Emphasizing Prehospital Administration of Methylene Blue.

We present the case of an 18-year-old male who was found unresponsive at home with profound cyanosis and shock. On-site suspicion of methemoglobinemia -suggested by chocolate-colored blood1 and refractory hypoxemia despite 100% oxygen - prompted early administration of methylene blue by emergency medical services. A second dose of methylene blue was given after patient's admission at the emergency department, resulting in a marked reduction in methemoglobin levels and rapid clinical improvement. This case highlights the importance of early recognition of toxicologic emergencies and timely administration of antidotes, including in the prehospital setting. It also underscores the need for ongoing education and training of health care professionals - especially first responders - on the identification and management of acute intoxications.