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

Its targeted mechanism makes it relevant in studies focused on weight management and metabolic health
The evidence is overwhelming, consistent, and reproduced across thousands of subjects in multiple rigorous trials
Inactive Recommended biochemical nomenclature restricts the term vitamin B 12 for cyanocobalamin