Serious vitamin B12 deficiency may result in anemia, stomach problems, and nerve damage.
is based on your medical condition and response to treatment. Injections may be given daily when you first start treatment. Certain medical conditions (e.g., pernicious anemia) may require you to continue receiving injections every month.
Pain/redness at the injection site, mild diarrhea, itching, or a feeling of swelling all over the body may occur.