Subcutaneous Injection: What Is It and How to Give One Ro Subcutaneous Injection: What Is It and How to Give One Ro L Carnitine Body Contouring Institute BCN Mesotherapy Serum Dermishop L Carnitine Injectable Factor Health MD Subcutaneous Injection: What It Is and How to Give One The How matters just as much as the What. We put together this step by step guide so you never have to guess what you need,where to inject and the mistakes to avoid.