A differential for the myelopathy would include various metabolic, toxic, immunologic, and infectious disorders, such as copper deficiency myelopathy (possibly precipitated by zinc toxicity), folate deficiency myelopathy, vitamin E deficiency myelopathy, nitrous oxide toxicity, HIV-related vacuolar myelopathy, HTLV-1-associated myelopathy, neurosyphilis, and possibly Lyme disease
In aged rodents, the same pharmacology has been extended to skeletal-muscle pathology, where it preserves muscle stem cell function and mitigates sarcopenia [3]
The most common ones are itchiness and diarrhea
For those with no known deficiencies or contraindications, vitamin B12 shots are often considered unnecessary and may not provide additional benefits