How to Give a B12 Injection: Step By Step Instructions IM Injection Intramuscular Injection What is IM Injection? Injection given deep into the muscle to ensure fast absorption of medication. .. . Common IM Injection Sites Deltoid Subcutaneous Injection: What It Is and How to Give One What is the most appropriate injection site for intramuscular injections? Injecting substances can expose individuals that use injection drugs to serious harm, but understanding the difference between safer and more harmful sites can help reduce these potential dangers. Here's a breakdown of