Curious about B12 shots? The Wellness Center How to self inject intramuscular vitamin B12 Overview Guy's and St Thomas' NHS Foundation Trust Vitamin B12 shots Prescription injections used to treat severe deficiency, pernicious anemia, or absorption issues (e.g., Crohn's, gastric bypass). They provide rapid, 100% absorption directly into the bloodstream, bypassing the digestive system. Vitamin B12 Injections Boost Energy & Wellness in Frankfort Vitamin B12 Injections Benefits & Where to Book Hydrate IV Bar