Relação entre o uso de metformina e a deficiência de vitamina B12 em pacientes com diabetes mellitus tipo 2

Objective: To analyze the prevalence of patients with Type 2 Diabetes Mellitus and hypovitamin and understand the clinical impacts of this correlation. Methods: DeCS was accessed to define and select the following descriptors: metformin, vitamin B12 and diabetes mellitus. In the databases PubMed, LILACS and SciELO, with the aid of search filters, 20 articles published in last 10 years. Results: Type 2 Diabetes Mellitus feared as the first risk, not treatment with metformin, which does not control blood glucose, helps with weight loss, reduces cardiovascular risk and deaths. On the other hand, there is significant evidence of an association between the use of metformin and vitamin B12 deficiency. This cobalamin hypovitaminosis results from interference with a calcium-dependent membrane responsible for the absorption of intrinsic vitamin B12 from the non-terminal ileum, resulting in neuropathies and megaloblastic anemias. Therefore, for this reason, it is important to perform or monitor two patients for vitamin therapy as needed. Final considerations: The selected studies will have a high prevalence of deficiency or possible hypovitaminase in metformin users. Finally, further studies on the clinical impacts of hypovitamin are necessary to elucidate the need for supplementation.