Background: Ingestion of cyanide may not manifest immediately in acute life-threatening symptoms. This delay presents an opportunity for recognition and appropriate management.

Case Report: A 23-year-old male purchased sodium cyanide through an internet order for suicidal gesture. He mixed sodium cyanide (5 grams) with cola soft drink (350 mL) to produce hydrogen cyanide. The patient inhaled cyanide gas for 30 minutes, however, he did not lose consciousness. He then drank the entire solution, causing him to vomit. The patient presented to the emergency medicine department about two hours after ingestion. He was conscious, and his vital signs were normal. Blood chemistries revealed wide anion gap metabolic acidosis (anion gap 16 mmol/L). Arterial blood gas and venous blood gas on arrival demonstrated no acidosis but narrow arterial and venous oxygen saturation gap (3%). He was treated with 12.5 grams of sodium thiosulfate intravenously, 50 grams of activated charcoal administered orally, and other supportive care. The patient condition improved clinically and laboratory. The narrow arterial-venous oxygen saturation gap was resolved (52%) at four hours post treatment. Hydrogen cyanide levels in patient’s plasma and urine samples were confirmed by Gas Chromatography Mass Spectrometry methods.

Conclusion: The patient was a confirmed case of acute cyanide poisoning, exhibiting the early signs of cyanide poisoning, and was successfully treated with sodium thiosulfate alone.

Keywords: Cyanide, Hydrogen Cyanide, Sodium thiosulfate, Cyanide levels