From the Research
The management of elevated vitamin B12 levels primarily involves identifying and treating the underlying cause rather than directly lowering B12 levels. First, discontinue any unnecessary vitamin B12 supplementation, including multivitamins or B-complex supplements containing cyanocobalamin or methylcobalamin. Common causes requiring investigation include liver disease, certain blood disorders like myeloproliferative neoplasms, solid organ malignancies, and kidney disease. Laboratory evaluation should include complete blood count, comprehensive metabolic panel, and possibly specific tests for conditions like polycythemia vera or chronic myelogenous leukemia if clinically suspected. No specific medication exists to lower B12 levels, as the body naturally eliminates excess through urine. Treatment focuses on addressing conditions like liver disease, kidney dysfunction, or blood disorders that may be causing the elevation. For example, if related to a myeloproliferative disorder, treatment might involve medications like hydroxyurea or ruxolitinib, as suggested by 1. It's also important to consider the role of macro-vitamin B12, which can cause falsely elevated cobalamin levels, as noted in 2. Additionally, the use of biomarkers such as total B12, holotranscobalamin, methylmalonic acid, and homocysteine can be helpful in establishing the diagnosis and cause of B12 deficiency, as discussed in 3. However, an unexpectedly high level of total B12 is most often of no clinical importance, though sometimes related to the presence of underlying cancer, as mentioned in 3. The most recent study, 4, found an association between elevated vitamin B12 levels and pediatric neurologic disorders, particularly epilepsy, highlighting the need for thorough investigation in cases of unexplained elevations. Overall, the approach to managing elevated vitamin B12 levels should prioritize identifying and treating the underlying cause, rather than focusing solely on lowering B12 levels, as supported by the highest quality and most recent evidence 4.