Cyanocobalamin (Vitamin B12)

Cyanocobalamin (Vitamin B12) is required for the maintenance of normal erythropoiesis, nucleoprotein and myelin synthesis, cell reproduction and normal growth. It is a coenzyme involved in metabolic functions including protein synthesis and carbohydrate metabolism. It plays a role in cell replication and hematopoiesis. Vitamin B12 deficiency is treated in conditions such as pernicious anemia, low intake from food, thyrotoxicosis, hemorrhage, malignancy, liver or kidney disease, gastric bypass surgery, gastrectomy, gluten enteropathy or sprue, folic acid deficiency, and macrocytic anemia.

• Pernicious anemia
• Vitamin B12 deficiency (low intake from food)
• Thyrotoxicosis
• Hemorrhagic anemia
• Malignancy-associated anemia
• Liver or kidney disease-related B12 deficiency
• Post-gastric bypass surgery or gastrectomy
• Gluten enteropathy or sprue
• Folic acid deficiency
• Macrocytic anemia

Vitamin B12 (cyanocobalamin) is required for the maintenance of normal erythropoiesis, nucleoprotein and myelin synthesis, cell reproduction and normal growth. It is a coenzyme; metabolic functions include protein synthesis and carbohydrate metabolism. Plays a role in cell replication and hematopoiesis.

Vitamin B12 (cyanocobalamin) is required for the maintenance of normal erythropoiesis, nucleoprotein and myelin synthesis, cell reproduction and normal growth. Plays a role in cell replication and hematopoiesis.

Adult Dose (IM - Pernicious or Macrocytic Anemia): 250-1000 mcg, given on alternate days for 1-2 weeks, then 250 mcg weekly until blood count returns to normal. Maintenance doses: 1000 mcg, given every month.

Hepatic Dose: Increased requirement in hepatic impairment.

Renal Dose: Increased requirement in renal impairment.

Administered as intramuscular injection. Take in the dose and duration as advised by your doctor.

If you miss a dose of Cyanocobalamin, please consult your doctor.

Common Side Effects (>10%):

• Arthralgia (joint pain) (12%)
• Dizziness (12%)
• Headache (12%)
• Nasopharyngitis (12%)

Other Side Effects:

• Anaphylaxis
• Angioedema
• Congestive heart failure
• Peripheral vascular disease
• Pulmonary edema
• Diarrhea
• Dyspepsia
• Polycythemia vera
• Sore throat
• Nervousness
• Rhinitis
• Glossitis
• Hypoesthesia

• Intensive treatment of B12-deficient megaloblastic anemia may cause hypokalemia and sudden death.
• Nasal disease: Defer use until symptoms resolve.
• Use with caution in patients with Leber optic nerve atrophy.
• Thrombocytosis may occur with treatment of severe vitamin B12 megaloblastic anemia.

• Leber's disease (Leber optic nerve atrophy)
• Tobacco amblyopia

Absorption reduced by antibiotics, aminosalicylic acid, anticonvulsants, biguanides, cholestyramine, cimetidine, colchicine, potassium salts, methyldopa.

Can be taken with or without food.

Pregnancy Category: A (for doses up to RDA); C (for doses exceeding RDA and for intranasal products).

Drug is distributed in milk; safe to use.

Pediatric dosage should be determined by a physician.

Limited information is available regarding dose adjustment for elderly patients.

Renal impairment: Increased requirement in renal impairment.

Hepatic impairment: Increased requirement in hepatic impairment.

Information on Vitamin B12 overdosage is not available. Overdose is generally not toxic as it is water-soluble and excess is excreted in urine.

Store in a cool and dry place, away from light. Keep out of reach of children.

Cyanocobalamin (Vitamin B12)