B12 Injection sites + How to use B12 Shots Safely PDF) Comparison of sublingual vs. intramuscular administration of vitamin B12 for the treatment of patients with vitamin B12 deficiency Efficacy of sublingual versus oral vitamin B12 supplementation for the treatment of vitamin B12 deficiencyA prospective randomised open label study Clinical Nutrition ESPEN 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