Best Vitamin B12 Injection Sites: Where to Inject B12 PA Relief Intramuscular Injection in Deltoid Muscle with Z Track Technique Compounded Methylcobalamin (Vitamin B12) Injection, 5mg mL Deltoid Muscle Injection The deltoid muscle is a common site for intramuscular (IM) injections, especially vaccines! What gauge needle do you use for an IM injection? Answer in the comments! #medicationadministration #IMinjection # Optimal B12 Injection Sites for Maximum Absorption and Benefits Your Health Magazine