thiamin free vitamin b12 injectable Penn Vet Dose Vial 2 mL is used to treat and prevent thiamine deficiency Rx Vitamin B-12 (Generic) Injectable
Description
Because it disrupts myelin maintenance and methylation-dependent neuronal processes

Your body can also store B-12 for future use

I have read that there is a risk of triggering depression and some memory issues

It also has a direct effect on immune function