B12 Shots: Vitamin B12 Injections Benefits, Uses, Risks Dr. Axe Why Do I Feel Worse After My B12 Injection? Causes & Management Bolt Pharmacy Vitamin B12: Overdose and Side Effects Vitamin B12 (cobalamin) and folate (vitamin B9) are vitamins that serve important functions in the human body. Folate is needed for development and growth of cells (including red blood cells) and synthesis Vitamin B12 Injections Greenway and Cippenham in Slough Serious Side Effects of Vitamin B12?