B12 Injection Dosage and Frequency: 7 Essential Guidelines for Adults Liv Hospital 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 Needles for B12 injections? Amazon.com: Ulove Prs 12 Pack 1ml Industrial Syringes with 25Ga 1 Inch Needle, Plastic Disposable Syringe and needle for Scientific Labs, Liquids Refilling and Measuring : Industrial & Scientific Not all shots are the same here's a guide Injections are a fast, effective way to deliver medications, nutrients, and vaccines directly into the bodybut not all injections are the