b12 injection rash Vitamin Side Effects P484 Cobalt as the culprit:
Description
it is the most readily absorbed and it remains in the body for a longer period of time and at higher levels than cyanocobalamin, which means that your body is supplied with vitamin B12 for longer if you use methylcobalamin than if you use cyanocobalamin
Causes of Vitamin B12 Deficiency Vitamin B12 deficiency can occur due to a range of dietary, medical, and lifestyle factors

[Google Scholar] 5.Aksoy S, Szumlanski CL, Weinshilboum RM

Reprint of Immunomodulatory effects of CD38-targeting antibodies
