can you take folic acid with b12 injections Vitamin and Folate : When Should them Together? – WhyNotNatural Folic Acid (Vitamin B9) Injection
Description
Is It Necessary To Have A Prescription For B12 Injections

doi: 10.1016/0165-6147(94)90118-x

They are not intended for human or animal use, bodily introduction, consumption, administration, therapeutic use, diagnostic use, cosmetic use, dietary supplement use, or any form of clinical application

So, if your vitamin B12 deficiency is due to an autoimmune disease in which your stomach doesn't make intrinsic factor, supplements might not work for you, and you will need injections

The intensity of the pink color correlates with B12 concentration
