Keep the product away from children and pets
PMID 35337622
While anyone experiencing a B12 deficiency can benefit from B12 shots, certain groups are more likely to need them, including: Vegans and vegetarians Elderly individuals Individuals with Crohns disease or celiac disease Individuals taking proton pump inhibitors or metformin which interfere with B12 absorption Side Effects and Precautions While Vitamin B12 shots are usually deemed safe, there might be some potential side effects, such as: Pain or redness at the injection site Mild diarrhea Headache Itching or rash In rare instances, individuals may encounter more intense reactions, like difficulty breathing or anaphylaxis
In such cases, you may be prescribed to take B-12 injections at home a couple of times per week, or as directed by your doctor
But the long-term safety is completely unproven , and there are plausible mechanisms by which things could go wrong (such as promoting tumor growth or causing unwanted tissue changes)
At ~300500 mcg/day, a 5 mg vial covers roughly 1016 days of dosing