Hydroxocobalamin

Hydroxocobalamin Brand Names- Cyanokit | Primabalt-RP

What is Hydroxocobalamin

Hydroxocobalamin is a parenteral preparation of vitamin B12; specifically, it is the hydroxylated active form of vitamin B12. Hydroxocobalamin is used to treat known or suspected cyanide toxicity.

Cyanide toxicity can occur from inhalation, ingestion, or exposure of the skin to various cyanide-containing compounds, including smoke inhalation from confined space fires.

Sources of cyanide toxicity include hydrogen cyanide and its salts, cyanogenic plants, aliphatic nitriles, and prolonged therapy with sodium nitroprusside.

Unlike other treatments for cyanide toxicity, amyl nitrite and sodium nitrite, hydroxocobalamin does not cause methemoglobinemia or hypotension. In addition, hydroxocobalamin has been shown to bind both intra- and extracellular cyanide.

Hydroxocobalamin is also used to treat megaloblastic anemia, pernicious anemia, and other states of vitamin B12 deficiencies.

Vitamin B12 is essential to growth, cell reproduction, hematopoiesis, and nucleoprotein and myelin synthesis.

Vitamin B12 is an essential vitamin found in foods such as meat, eggs, and dairy products. Deficiency in healthy individuals is rare; the elderly, strict vegetarians (i.e., vegan), and patients with malabsorption problems are more likely to become deficient.

If vitamin B12 deficiency is not treated with a vitamin B12 supplement, then anemia, intestinal problems, and irreversible nerve damage may occur. Oral therapy is not always effective, as some persons lack intrinsic factor, an endogenous substance produced by the stomach and necessary for oral B12 absorption.

Other patients may not be able to absorb oral vitamin B12 due to surgical removal or dysfunction of the intestines in the area where absorption of vitamin B12 occurs.

Thus, parenteral therapy may be required.

Hydroxocobalamin was FDA-approved in 1975.

Cyanokit was FDA approved December 2006.

Indications

  1. cyanide toxicity
  2. homocystinuria
  3. macrocytic anemia
  4. pernicious anemia
  5. vitamin B12 deficiency
  6. vitamin B12 deficiency diagnosis
  7. vitamin B12 deficiency megaloblastic anemia

NOTE: Hematocrit, reticulocyte count, vitamin B12, folate, and iron concentrations should be obtained prior to treatment. If folate concentrations are low in a patient with low B12 concentrations, folic acid should only be administered in combination with B12 (see Contraindications). Vitamin blood concentrations and peripheral blood counts should be monitored at one month of treatment and then at intervals of 3—6 months.

Side Effects

  1. abdominal pain
  2. anaphylactoid reactions
  3. crystalluria
  4. diarrhea
  5. dizziness
  6. dyspepsia
  7. dysphagia
  8. dyspnea
  9. edema
  10. erythema
  11. headache
  12. hot flashes
  13. hypertension
  14. injection site reaction
  15. lymphopenia
  16. nausea
  17. peripheral edema
  18. pleural effusion
  19. pruritus
  20. rash
  21. renal failure (unspecified)
  22. renal tubular necrosis
  23. restlessness
  24. shivering
  25. skin discoloration
  26. urine discoloration
  27. urticaria
  28. ventricular tachycardia
  29. vomiting

Monitoring Parameters

  • blood pressure
  • hemoglobin/hematocrit
  • platelet count
  • reticulocyte count
  • serum creatinine/BUN
  • serum iron
  • serum potassium

Contraindications

  • breast-feeding
  • children
  • dialysis
  • folate deficiency
  • hypertension
  • hypokalemia
  • infection
  • iron-deficiency anemia
  • polycythemia vera
  • pregnancy
  • renal failure
  • renal impairment
  • thrombocytosis
  • uremia

Interactions

  • Bacillus Calmette-Guerin Vaccine, BCG
  • Colesevelam
  • Phenicol Derivatives