Pyridoxine: Pyridoxine should not be administered to patients already receiving levodopa, because it is an antagonist of pyridoxine
It occurs more commonly in people who have other autoimmune diseases
People prefer subcutaneous injection when administering small amounts of medicines or vitamins, such as vitamin B12, at home

Your doctor will conduct a comprehensive clinical assessment including: Detailed medication and supplement history , including over-the-counter vitamins and injections Review of symptoms suggesting liver, kidney, or haematological disease Physical examination for hepatomegaly, splenomegaly, jaundice, or lymphadenopathy Additional blood tests , such as full blood count, liver function tests, renal function, and inflammatory markers Depending on initial findings, further investigations may include: Liver ultrasound or imaging if hepatic pathology is suspected Haematology referral for blood film examination, bone marrow biopsy, or specific tests for myeloproliferative disorders Measurement of holotranscobalamin or methylmalonic acid if functional B12 status needs clarification despite high total B12 Targeted investigations based on clinical findings and following NICE guidance for suspected serious conditions Treatment focuses on addressing the underlying cause rather than the elevated B12 itself

What has NICE done