What Happens If You Inject B12 Wrong: 6 Red Flags CYANOCOBALAMIN INJECTION, USP 30000 mcg 30 mL (1000 mcg mL) 30 mL VIAL B12 Shot Guide: Benefits, Dosage & Side Effects BodySpec Vitamin B12 Hydroxocobalamin Injection HAIM International VITAMIN B12 INJECTION Vitamin B12 is an essential component that plays an important role in the metabolism of carbohydrates and fats, as well as red blood cell production. It is very effective in NEW TREATMENT ALERT A vitamin B12 injection helps treat or prevent deficiency by delivering the vitamin directly into the bloodstream. It's often used for people with absorption issues and is usually safe