From the Guidelines
Treatment for Vitamin B12 Deficiency-Induced Pernicious Anemia
The treatment for vitamin B12 deficiency-induced pernicious anemia should start with intramuscular injections of hydroxocobalamin, with a dose of 1 mg administered on alternate days until there is no further improvement for patients with neurological involvement, and three times a week for 2 weeks for those without neurological involvement, followed by maintenance treatment with 1 mg intramuscularly every 2–3 months for life 1.
- Initial Treatment: For patients with neurological involvement, hydroxocobalamin 1 mg intramuscularly should be administered on alternate days until there is no further improvement 1.
- Maintenance Treatment: After the initial treatment, maintenance therapy with hydroxocobalamin 1 mg intramuscularly every 2–3 months is recommended for life, regardless of neurological involvement 1.
- Monitoring: It is essential to monitor the patient's complete blood count, reticulocyte count, and serum vitamin B12 levels to assess the response to treatment and adjust the dose and frequency as needed.
- Lifelong Treatment: Patients with pernicious anemia may require lifelong treatment, and regular follow-up appointments are necessary to ensure that the condition is well-managed.
- Specialist Advice: For patients with possible neurological involvement, such as unexplained sensory and/or motor and gait symptoms, urgent specialist advice from a neurologist and haematologist should be sought 1.
From the FDA Drug Label
In patients with Addisonian Pernicious Anemia, parenteral therapy with vitamin B12 is the recommended method of treatment and will be required for the remainder of the patient’s life. Treatment of Vitamin B12 Deficiency Thirty mcg daily for 5 to 10 days followed by 100 to 200 mcg monthly injected intramuscularly.
The treatment for Vitamin B12 deficiency-induced pernicious anemia is parenteral therapy with vitamin B12, which is required for the remainder of the patient's life. The recommended dosage is:
- 30 mcg daily for 5 to 10 days
- Followed by 100 to 200 mcg monthly injected intramuscularly 2 Patients with pernicious anemia should be informed that they will require monthly injections of vitamin B12 for the remainder of their lives 3.
From the Research
Treatment Options for Vitamin B12 Deficiency-Induced Pernicious Anemia
- Oral vitamin B12 supplementation is a viable treatment option for pernicious anemia, with studies showing significant improvement in vitamin B12 deficiency-related features 4, 5, 6, 7.
- The recommended dosage for oral vitamin B12 supplementation is 1000 μg/d, which has been shown to improve vitamin B12 deficiency in patients with pernicious anemia 4, 5, 7.
- Oral vitamin B12 replacement has been found to be an effective alternative to intramuscular vitamin B12 injections, with advantages including reduced need for injections and potential for improved patient compliance 5, 7.
- Clinical and biological parameters, such as plasma vitamin B12, plasma homocysteine, and plasma methylmalonic acid concentrations, have been shown to improve significantly with oral vitamin B12 supplementation 4, 8, 6.
- The time to reverse initial vitamin B12 deficiency abnormalities has been reported to range from 1 month for hemolysis to 4 months for mucosal symptoms 4.
- Oral intermittent therapy has been found to be useful for maintaining a normal serum vitamin B12 concentration, with a 7-day regime of administration needed every 1-3 months 6.
Comparison with Intramuscular Vitamin B12 Injections
- High oral doses of vitamin B12 (1000 mcg and 2000 mcg) have been found to be as effective as intramuscular administration in achieving haematological and neurological responses 7.
- Oral vitamin B12 supplementation has been shown to be a viable alternative to intramuscular injections, with potential advantages including reduced discomfort and improved patient compliance 5, 7.