Vitamin Injections vs. Oral Supplements: What's the Difference? Vital Flow Infusions Lipotropic Vitamin Injections vs. Oral Supplements Vitamin B 12 intramuscular injections are also used therapeutically to help restore energy and combat various symptoms related to such deficiencies. Vitamin B 12 is essential to the development of healthy blood cells, nerve B12 Injections vs Oral Supplements: Which Is Better for Energy and Deficiency?