How Often Should You Get Vitamin B12 Injections? Compounded Hydroxocobalamin (Vitamin B12) Injection Cyanocobalamin (B12) Injection 1000 mcg mL, Multiple Dose Vial 30 mL McGuff Always Tired? B12 Injections Could Help Main benefits of B12 injections 1) Increased energy & reduced fatigue B12 helps convert food into usable energy Deficiency often causes tiredness, weakness, and low stamina 2) Healthy red blood cells Prevents B 12 Injections Specialists in San Antonio, TX