From the Guidelines
The recommended dosage of Vitamin B12 (Cobalamin) for individuals with deficiency is hydroxocobalamin 1 mg intramuscularly administered three times a week for 2 weeks, followed by maintenance treatment with 1 mg intramuscularly every 2–3 months for life, as stated in the British Obesity and Metabolic Surgery Society guidelines 1.
Key Considerations
- For individuals with vitamin B12 deficiency and possible neurological involvement, treatment should be initiated immediately with hydroxocobalamin 1 mg intramuscularly on alternate days until there is no further improvement, then administered every 2 months 1.
- It is essential to treat vitamin B12 deficiency before initiating folic acid supplementation to avoid masking underlying vitamin B12 deficiency and precipitating subacute combined degeneration of the spinal cord 1.
- Maintenance treatment with hydroxocobalamin 1 mg intramuscularly every 2–3 months is recommended for life to prevent recurrence of deficiency 1.
Important Notes
- Vitamin B12 deficiency can be caused by various factors, including malabsorption, dietary deficiencies, and certain medications, and it is crucial to identify and address the underlying cause of deficiency 1.
- Individuals with vitamin B12 deficiency may present with megaloblastic, macrocytic anemia, and neurological symptoms, such as unexplained sensory and/or motor and gait symptoms, and should be referred to a neurologist and hematologist for urgent specialist advice 1.
From the FDA Drug Label
1 mg per day may result in hematologic remission in patients with vitamin B12 deficiency. Doses of cyanocobalamin exceeding 10 mcg daily may produce hematologic response in patients with folate deficiency. Amounts of vitamin B12 that are recommended by the Food and Nutrition Board, National Academy of Science-National Research Council for pregnant women (4 mcg daily) should be consumed during pregnancy. Amounts of vitamin B12 that are recommended by the Food and Nutrition Board, National Academy of Science-National Research Council for lactating women (4 mcg daily) should be consumed during lactation. Intake in children should be in the amount (0.5 to 3 mcg daily) recommended by the Food and Nutrition Board, National Academy of Science-National Research Council.
The recommended dosage of Vitamin B12 (Cobalamin) is as follows:
- Pregnant women: 4 mcg daily 2
- Lactating women: 4 mcg daily 2
- Children: 0.5 to 3 mcg daily 2
- Patients with vitamin B12 deficiency: 1 mg per day may result in hematologic remission 2
- Patients with folate deficiency: doses exceeding 10 mcg daily may produce hematologic response 2
From the Research
Recommended Dosage of Vitamin B12
The recommended dosage of Vitamin B12 (Cobalamin) varies depending on the patient's condition and the route of administration.
- For parenteral regimens, a dosage of 1000 micrograms cyanocobalamin is recommended, with 5 or 6 biweekly injections for loading, and once-a-month for maintenance 3.
- For oral therapy, a dosage of 300-1000 micrograms per day may be therapeutically equivalent to parenteral therapy 3.
- High-dose oral vitamin B12 (1 to 2 mg daily) is as effective as intramuscular administration for correcting anemia and neurologic symptoms 4.
- For patients who have had bariatric surgery, a dosage of 1 mg of oral vitamin B12 per day indefinitely is recommended 4.
- For maintenance therapy, a dosage of 125 to 250 µg for patients with dietary insufficiency and 1 mg daily for those with pernicious anaemia is suggested 5.
- Oral supplementation with 1000 μg/d of cyanocobalamin has been shown to improve vitamin B12 deficiency in pernicious anemia 6.
- Daily oral cyanocobalamin at doses of 1000-2000 microg can be used for treatment in most cobalamin-deficient patients who can tolerate oral supplementation 7.