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Poisoning Information for the Public & Health Care Professionals
Last updated: 07/2015



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  • Cyanide poisoning from hydrogen cyanide gas (smoke inhalation), ingestion of cyanide salts, high dose nitroprusside infusion.
  • May be used alone or in combination with sodium thiosulfate.


  • Initial dose: 70 mg/kg (not to exceed 5 g) over 15 minutes.
  • Depending on severity of poisoning and clinical response, the same dose may be repeated once. The rate of infusion for the second dose may range from 15 minutes to 2 hours as clinically indicated.
  • Dosing is suitable for infants to adolescents. Do not exceed 5 g in patients greater than 70 kg. 


  • Reconstitution: For a final concentration of 25 mg/mL: reconstitute each 2.5 g vial with 100 mL sodium chloride 0.9% or each 5 g vial with 200 mL sodium chloride 0.9%. Use the transfer spike provided. Rock or invert the vial for at least 1 minute to mix. Do not shake.
  • Infusion: Administer the reconstituted dose over 15 minutes. Use administration set provided as it contains the appropriate filter. Also included in each kit is a short catheter (needle) for pediatric administration. The provided administration set can be piggybacked into a primary line. Blood pressure monitoring is required.

Compatibility, Stability

  • Compatible with sodium chloride 0.9% (recommended), dextrose 5% in water and lactated ringer’s.
  • Do not administer other drugs, especially sodium thiosulfate, in the same line as hydroxocobalamin.
  • Once reconstituted, the vial is stable for 6 hours at room temperature.
  • Reconstituted solution should be dark red in colour.
  • Protect vials from light.

Potential Hazards of Administration

  • Hypertension (transient; returns to baseline within 4 hours of dose).
  • Nausea, Headache, Dizziness.
  • Red discolouration of the urine (pronounced for 3 days following dose; may last up to 5 weeks)
  • Erythema of skin or mucous membranes (may last up to 2 weeks), pustular rash mainly affecting the face and neck  (usually 7 - 28 days following treatment).
  • Allergic reactions (including anaphylaxis, chest tightness, edema, urticaria, pruritus, dyspnea and rash).


  • Hydroxocobalamin may interfere with some clinical chemistry assays such as:

    - aminotransferases, bilirubin, creatinine, creatine kinase, phosphorus, magnesium, lactate

    - Co-oximetry readings such as carboxyhemoglobin, methemoglobin, which may be of significant clinical consequence in the setting of smoke inhalation

  • Hydroxocobalamin may trigger blood leak alarms on certain hemodialysis machines, likely due to colorimetric interference

Bailey, B., Blais, R., Gaudreault, P., Gosselin, S., & Laliberte, M. (2009). Antidotes en toxicologie d'urgence (3rd ed.). Quebec, Canada: Centre antipoison du Quebec.

Borron, S. W., Bronstein, A. C., Fernandez, M. C., & et all. (2014). Walter F. G. (Ed.), AHLS advanced hazmat life support, provider manual (4th ed.). Tucson, Arizona: The University of Arizona College of Medicine.

Brunel, C., Widmer, C., Augsburger, M., Dussy, F., & Fracasso, T. (2012). Case report: Antidote treatment for cyanide poisoning with hydroxocobalamin causes bright pink discolouration and chemical-analytical interferences. Forensic Science International, 223, 10-12.

Goldfrank, L. R., Nelson, L. S., Lewin, N. A., Howland, M. A., Hoffman, R. S., (2015). Goldfrank's toxicologic emergencies(Tenth ed.). New York: McGraw Hill.

Hall, A. H., Saiers, J., & Baud, F. (2009). Review article: Which cyanide antidote. Critical Reviews in Toxicology, 39(7), 541-552.

Merck, S. (2012). Cyanokit, hydroxycobalamin package insert. online. Retrieved from http://www.cyanokit.com/prepare.aspx

Micromedex, T. H. A. (2014). Micromedex health care systems. Retrieved from http://www.micromedexsolutions.com

Mintegi, S., Clerigue, N., Tipo, V., Ponticiello, E., Lonati, D., Burillo-Putze, G., & Delvau, N. (2013). Pediatric cyanide poisoning by fire smoke inhalation: A european expert consensus. Pediatric Emergency Care, 29(11), 1234-1240.

Olson, K. R. (2007). Poisoning & drug overdose (Sixth ed.). New York: McGraw Hill.

Phelps SJ, C. C. (2013).  Teddy bear, pediatric injectable drugs. Retrieved from http://www.pharmpress.com/product/MC_PED/pediatric-injectable-drugs

Reade, M. C., Davies, S. R., Morley, T. M., & Jacobs, I. C. (2012). Review article: Management of cyanide poisoning. Emergency Medicine Australasia, 24, 225-238.

Shannon, M. W., Borron, S. W., & Burns, M. J. (2007). Haddad and Winchester's clinical management of poisoning and drug overdose (Fourth ed.). Philadelphia: Saunders Elsevier.

Smollin, C. G. (2010). Toxicology: Pearls and pitfalls in the use of antidotes. Emergency Medicine Clinic of North America, 28, 149-161.

Stellpflug, S. J., Gardner, R. L., Leroy, J. M., Ellsworth, H., & Zwank, M. D. (2013). Letter to editor: Hydroxocobalamin hinders hemodialysis. American Journal of Kidney Dialysis, 62, 395.

Stretz, M. J., Bebarta, V. S., Borys, D. J., & Morgan, D. L. (2014). Patterns of cyanide antidote use since regulatory approval of hydroxocobalamin in the United States. American Journal of Therapeutics, 21, 244-249.

Sutter, M. E., Clarke, M. E., Cobb, J., Daubert, G. P., Rathore, V. S., Aston, L. S., . . . Albertson, T. E. (2012). Blood leak alarm interference by hydroxocobalamin is hemodialysis machine dependent. Clinical Toxicology (Philadelphia, Pa.), 50, 892-895.

Thompson, J. P., & Mara, T. C. (2012). Hydroxocobalamin in cyanide poisoning. Clinical Toxicology (Philadelphia, Pa.), 50(10), 875-885.