Vitamin B12 Injections
B12 injections are a treatment for vitamin B12 deficiency, given as hydroxocobalamin, starting with frequent injections and then transitioning to less frequent maintenance doses. These shots are often a few times a week initially, then potentially every few months, depending on your symptoms and blood test results. Common side effects include pain or swelling at the injection site, and while treatment can provide quick B12 level support, it may take days or weeks for symptoms to fully improve.
Treatment Schedule & Dosage
Initial treatment: You will likely start with injections a few times a week for a short period to quickly boost your B12 levels. A common initial schedule is every other day for two weeks, or until symptoms improve.
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Maintenance: The frequency of injections decreases over time. Once your symptoms and B12 levels improve, you may receive injections less often, such as every few months.
Effectiveness and onset of symptoms
Quick action: Injections can start working straight away to raise B12 levels, bypassing potential issues with oral absorption.
Symptom improvement: It can take a few days or even weeks to feel the full benefits of the treatment, even after the injections begin.
Potential side effects
Common side effects: Mild pain, swelling, or itching at the injection site are common and usually temporary.
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Other side effects: Some people may experience feeling sick or diarrhea. Headaches and tiredness have also been reported.
Long-term use and alternatives
Long-term necessity: Many people with certain conditions, like pernicious anemia, will need lifelong B12 injections.
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Diet-related deficiency: If your deficiency is purely diet-related, you may eventually be able to switch to daily vitamin B12 tablets or receive less frequent injections (e.g., twice a year).