Best Vitamin B12 Injection Site: Administering B12 Shots Taylor demonstrates the proper technique for administering an intramuscular injection. Locate the upper, outer quadrant of the buttock muscle Prepare the site with alcohol Insert needle all the B12 Injections at Home Safety Guide for Self Administration Infusion For Health Vitamin B1, B6, B12. Buttock injection Push Ep 04 @InjectionTips1 B 12 (Methylcobalamin) Therapy MedClub by Dr Jenn