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 bodybut not all injections are the Best Vitamin B12 Injection Sites: Where to Inject B12 PA Relief B12 vitamin Store Intramuscular vs Subcutaneous Injections for vitamin B12 supplements. Subcutaneous (SC) and Intramuscular (IM) Injections Must Knows for Subcutaneous administration: Pinch skin with non dominant hand and hold syringe with dominant hand Always inject: 2 inches away from umbilicus (for abdomen) 3 inches B12 vitamin Store Intramuscular vs Subcutaneous Injections for vitamin B12 supplements.