Seek medical attention promptly if you experience symptoms that could suggest serious underlying conditions, including: Unexplained weight loss or persistent fatigue Jaundice (yellowing of skin or eyes), abdominal pain, or swelling Easy bruising or bleeding , or unusual skin rashes Night sweats , fever, or enlarged lymph nodes Reduced urine output , significant swelling in legs or ankles Persistent itching without obvious skin cause These symptoms may indicate liver disease, haematological disorders, or renal impairmentconditions that can elevate B12 and require specialist assessment

Common experiences after the first injection include: Mild soreness or redness at the injection site (usually resolves within 12 days) Slight improvement in energy levels or mood No immediate noticeable change (particularly common if deficiency is severe) Rarely, mild side effects such as headache or dizziness Some patients report their urine becoming brighter or more intensely coloured following injection, which occurs because excess B12 is excreted renally
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While many people get enough B12 from their food, others benefit from Vitamin B12 injections to fix a deficiency or boost their health