Best Vitamin B12 Injection Sites: Where to Inject B12 PA Relief Subcutaneous vs intramuscular what's the difference? #vitamintherapy #theb12store #injection Understanding the 4 main types of injections makes medical knowledge simple and clear. Intramuscular, Subcutaneous, Intradermal & Intravenous each one plays a different role in treatment. Stay informed, stay safe! Learn how to administer your own SubQ (subcutaneous) injections at home with confidence. Our step by step guide covers everything you need to know, from preparing your supplies to safely injecting the medication. Our 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 )