Semaglutide with B12 for Weight Loss: What Results to Expect Dr. Brandon Richland, MD Optimal B12 Injection Sites for Maximum Absorption and Benefits Your Health Magazine Types of Injection Injection is a method of administering medication directly into the body using a needle and syringe. It allows fast and effective absorption of medicines. Intradermal (ID) How to Give Yourself Intramuscular (IM) Injections Patients & Families UW Health B12 vitamin Store How to inject B12 in your arm