Ivy Grove Surgery : Self administration of B12 injection B12 Injections for Energy: Benefits and How It Works AZ IV Medics A little insight to the importance of the b12 injections. My client hadn't been feeling well & had some bloods done with her GP. The results identified a severe deficiency in b12. Not all shots are the same here's a guide Injections are a fast, effective way to deliver medications, nutrients, and vaccines directly into the body but not all injections are the same.