Efficacy of different routes of vitamin B12 supplementation for the treatment of patients with vitamin B12 deficiency: A systematic review and network meta analysis Irish Journal of Medical Science (1971 ) B12 Injections vs. Oral Supplements: Which Is Better? B12 Shot Guide: Benefits, Dosage & Side Effects BodySpec Oral vs. Intramuscular Vitamin B12 in Vitamin B12 Deficiency The Blood Project B12 Shots vs. IV Infusions: What is the difference? Integrative Medicine, Laser and Aesthetics Still taking vitamin B12 injections? Move over shot. A pill may be just as good. Dr. Leslie Greenberg's Blog