Is intramuscular (IM) administration of vitamin B12 injections preferred over subcutaneous (SC) administration? How to self administer subcutaneous B12 injection., 1. Withdraw proper dosage from vial into an insulin syringe, 2. Clean site of injection (abdomen or other proper site), 3. Pinch the skin where you Are you feeling run down? Low Energy? A quick Vitamin B12 injection can help support energy, metabolism, and overall wellness. It delivers the vitamin directly into the muscle, allowing your body to Vitamin B12 Subcutaneous Injection What Happens If You Inject B12 Into Fat? PA Relief