It is created using solid phase peptide synthesis, which adds an additional tyrosine to the N-terminal
Also, patients should be warned about the danger of taking folic acid in place of vitamin B12, because the former may prevent anemia but allow progression of subacute combined degeneration
The injection is well tolerated by most people, and some do not feel it
How often should vitamin B12 injections be administered during the initial treatment phase
Feeling tired, following a vegan or vegetarian diet, or wanting to improve general wellbeing does not by itself show that an injection is needed
This is because B12 is not a standard medication in the US or UK, so it is often made in small-scale compounding pharmacies rather than in large-scale manufacturing facilities