Possibilities of having high vitamin B12 in blood are very limited. 1. Are you on any Vitamin supplement... 2. Was the blood sample drawn after a meal 3. Check your hemoglobin and Bilirubin values, if they are normal you need not worry. I mean the only pathological condition that can produce high vitamin B12 level is HEMOLYSIS. B12 is a water soluble vitamin and there is no harm associated with excess of it inside our body. In fact body stores of B12 are sufficient for almost a year. Some very very metabolic problems can also have this picture, for further clarification, I need the following, CBC report, Folate level, LFT report, etc.