Yaowa Quiz | Will long-term use of sitagliptin and metformin tablets lead to vitamin B12 deficiency?

Sitagliptin metformin tablets contain metformin, which can cause vitamin B12 deficiency, but the mechanism is still unclear. Some studies believe that the absorption of the complex formed by vitamin B12 and intrinsic factor on the surface of ileal cells is a calcium-dependent absorption process. Metformin and its protonated biguanide group bind to the B12-intrinsic factor complex, which can change the membrane potential and competitively exclude calcium ions, leading to poor absorption of vitamin B12. Some studies also believe that metformin affects intestinal peristalsis, stimulates intestinal bacterial overgrowth, and competitively inhibits vitamin B12 absorption. In particular, some elderly patients who have taken metformin for a long time (more than 3 years) and those over 60 years old are more likely to lack vitamin B12. Therefore, patients who take metformin-containing drugs for a long time are advised to eat more foods rich in vitamin B, such as lemons, apples, etc., and supplement vitamin B12 through drugs when necessary.