what happens if you inject b12 into vein Semaglutide IV Injection: Why Subcutaneous Is Safer B12 Shots vs. IV Infusions:

Researchers often evaluate this material in controlled environments that require consistency, clear documentation, and dependable sourcing

If you are going to self-administer at home, your healthcare provider or nurse will teach you proper technique

Various neurological symptoms with vitamin B12 deficiency and posttreatment evaluation

Even if the product could be reclassified to make it available for sale in pharmacies, it could not be used more frequently than every 2 3 months, so reclassification to a Pharmacy medicine would not help those who require more frequent injections. and then they also state: Our current advice to private clinics administering vitamin B12 injections which are not licensed medicinal products intravenously for non-medicinal purposes is that we do not regard these to be medicines and that they fall outside of the remit of the MHRA

info please What a great experience

Inject intramuscularly