Vitamin B12: Understanding Deficiency and Supplementation Diet vs Disease Vitamin B12 Deficiency? Heres the best way to treat it!, Many people take oral or sublingual tablets, but they may not always be effective especially if absorption is poor., The active injectable Vitamin B12 Cyanocobalamin Injection 1000 mcg mL 1 mL Med Plus Physician Supplies Compounded Hydroxocobalamin (Vitamin B12) Injection