At Home Vitamin B12 4 Week Injection Package MUST BE A FLORIDA RESID CardioMender, MD Vitamin B 12 Injection, 3,000 mcg mL 100 mL Luminous B12 Injections What is a B12 injection A B12 injection is a form of supplementation where vitamin B12 is administered directly into the muscle or under the skin, bypassing Still taking vitamin B12 injections? Move over shot. A pill may be just as good. Dr. Leslie Greenberg's Blog