Best Vitamin B12 Injection Sites: Where to Inject B12 PA Relief How to Give B12 Injections at Home to Yourself PA Relief 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 How to Self Inject Vitamin B12 at Home The Sanctuary Wellness Institute How to Self Administer Subcutaneous & Intramuscular Injections Subcutanous injection self administration South Tees Hospitals NHS Foundation Trust