There are many reasons why you may be low on vitamin B12, but treatment for these symptoms is fairly easy
Skin signs that may suggest the dose is high for your body include a widespread rash beyond the injection site, persistent swelling that does not clear between weekly doses, or new hives away from the injection point
These figures come from preclinical and pharmacokinetic literature, not from approved human dosing and note the standard route for this molecule is oral
Redness, mild swelling, tenderness, or slight bruising can occur where the peptide is administered
This can include decreased stomach acid, which affects absorption, and diets low in animal products or high in processed food
Systemic side effects may occur in some individuals