You may wonder why we pull back into the syringe when giving injections in the vein. This picture explains why. We don't pull back to make sure we're in the vessel, we What Happens if You Inject Vitamin B12 Wrong? How to self inject intramuscular vitamin B12 Overview Guy's and St Thomas' NHS Foundation Trust How to Inject B12 into Fat: Steps, Sites & Safety Tips Injecting substances can expose individuals that use injection drugs to serious harm, but understanding the difference between safer and more harmful sites can help reduce these potential dangers. Here's a breakdown of B12 Injections at Home Safety Guide for Self Administration Infusion For Health