Vitamin B12 A Vitamin B12 injection is a quick shot that gives your body vitamin B12 directly into the muscle. This helps your body absorb it faster than tablets. Vitamin B12 helps Vitamin B 12 Injection for Animals, 3000 mcg mL, 100 mL Vial Prescription Medication for Pets Benefits of B12 Injections for Optimal Health Cyanocobalamin vs Hydroxocobalamin (Vitamin B12 forms) Key Clinical Differences Hydroxocobalamin is preferred in: Pernicious anemia Severe vitamin B12 deficiency Neurological symptoms (subacute combined degeneration, neuropathy) Cyanocobalamin is