If you are administering vitamin B12 injections at home, there are specific instructions you need to remember
Laboratory Testing Before starting Vitamin B12 injections, laboratory testing is often recommended to determine your baseline B12 levels and to monitor your progress
for personal research purposes but not for medical prescription
Contact your GP if you experience: Unexpected symptoms after starting B12 supplementation, including persistent skin reactions, gastrointestinal disturbance, or mild allergic manifestations Neurological symptoms such as significant tingling, numbness, weakness, or balance problemsthese may indicate B12 deficiency paradoxically, or alternative neurological conditions requiring assessment Unexplained fatigue or malaise that develops or worsens despite supplementation Concerns about medication interactions , particularly if taking metformin, proton pump inhibitors, or other medications affecting B12 metabolism [2] [4] Seek emergency medical attention (call 999) if you develop signs of a severe allergic reaction following B12 injection, including facial swelling, difficulty breathing, or widespread urticaria