Needle Sizes Explained: Choosing the Right Gauge for Different Injections HOW TO SELF INJECT B12 AT HOME with Dr. Tyler Rogers If you've been prescribed vitamin B12 shots or exploring at home wellness, this step by step guide will walk you through how Choosing the Right Needle and Syringe for B12 Injections: A Complete Guide How to draw up Lipotropic (labeled as MIC B12) Injections Transformations Weight Loss Does size matter? Historically, a bigger needle gauge was considered better to prevent damage to red blood cells. However, our recent guidelines recommend using smaller gauge needles (2325 G) for all Ivy Grove Surgery : Self administration of B12 injection