VanishPoint 29 Gauge x 5 16 inch Retractable Insulin Syringe with Needle 1 mL, Regular Wall, 100 Box Vitamin B12 Injection Dosage Guide: 7 Essential Dosage Facts for Adults Liv Hospital Is this the right size needle for im injections? : r B12_Deficiency Injection Syringe: Different Types Engiomed 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