long term side effects of b12 injections How Vitamin Affect Your Body: Good or Bad? 5 side effects of excessive

A 2025 European Journal of Clinical Nutrition commentary on the NICE guideline argued that the diagnostic threshold and clinical awareness still need to be tightened further, especially around pernicious anaemia, which is still under-recognised in primary care

However, it is not FDA-approved for medical treatment or injection, and regulatory status may vary by use

Following manufacturer or compounding pharmacy instructions for reconstitution is essential

Unlike oral supplements that have to go through the digestive system before reaching the bloodstream, a vitamin B12 injection delivers the nutrient directly into the blood

PMID 25117994

This remains anecdotal rather than research-validated but worth considering for those who track cycles