> There is one and only one indication for parenteral cyancobalamin (B12) administration and that is deficiency thereof due to inadequate production of gastric

> There is one and only one indication for parenteral cyancobalamin (B12) administration and that is deficiency thereof due to inadequate production of gastric intrinsic factor or a disease of the terminal ileum. Period. You are aware of a study of B12 injections in non-deficient individuals indicating no benefit? "No evidence" is not the same thing as "evidence against".