Based on current scientific reports, vitamin B12 (cobalamin), used in the treatment of pernicious anemia, may be used as a pain reliever. It has been shown to be effective in the treatment of different sorts of pain, including diabetic neuropathic, musculoskeletal, abdominal, back and spine ones, but also pain in Alzheimer's disease and pain ailments resulting from the development of neoplasms. In addition, it helps regeneration of the sensory nerves and relieves pain in eye diseases, for example in dry eye syndrome. This review summarizes recent research reports on pain-relieving properties of vitamin B12.