Hydroxocobalamin Dosing for Cyanide Toxicity

Introduction to Hydroxocobalamin Treatment

The American Heart Association recommends hydroxocobalamin as the primary antidote for cyanide poisoning because it does not cause hypotension or impair oxygen-carrying capacity, which is critical in cases of smoke inhalation with potential carbon monoxide co-poisoning 2, 7

For adults with suspected cyanide poisoning, administer 5 g of hydroxocobalamin IV, increasing to 10 g for cardiac arrest 1, 2
Standard dose: 5 g IV for suspected cyanide poisoning with severe manifestations (cardiac or respiratory arrest, shock, coma) 1, 3
Cardiac arrest dose: 10 g IV when the patient is in cardiac arrest from cyanide toxicity 1, 4

For children with moderate to severe cyanide poisoning, administer 70 mg/kg IV of hydroxocobalamin (maximum 5 g) 1, 3, 5

Infuse the initial 5 g dose of hydroxocobalamin over 15 minutes 2
Consider plasma lactate levels to guide treatment: lactate ≥8 mmol/L in pure cyanide poisoning or ≥10 mmol/L in fire victims without severe burns suggests significant cyanide toxicity 1

Add sodium thiosulfate 12.5 g IV for adults (250 mg/kg for children) following hydroxocobalamin to enhance cyanide elimination 2, 6
Administer 100% oxygen concurrently, as it accelerates carboxyhemoglobin elimination and counteracts cyanide's mitochondrial effects 2, 6

Hydroxocobalamin can cause oxalate nephropathy; monitor renal function 1, 3
Do not delay treatment for laboratory confirmation; clinical suspicion (fire exposure, altered mental status, metabolic acidosis, elevated lactate) warrants empiric administration of hydroxocobalamin 1
Administer hydroxocobalamin when patients present with smoke inhalation plus cardiovascular collapse, shock, or coma 1, 3
Administer hydroxocobalamin in cases of cardiac or respiratory arrest in fire victims 1, 4
Depressed mental status, seizures, or neurological deterioration are indications for hydroxocobalamin administration 2, 7