Consequences of Excess or Deficiency of Vitamin B12 Vinmec 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 Is It Okay To Use A B12 Injection With Insulin Syringes? Red Liquid Vitamin B12 in a Disposable Syringe with a Needle and in a Glass Ampoule on a White Background. Stock Photo Image of concept, injection: 252798588