How Vitamin B12 interacts with Biguanides

Interaction type: Depletions

Interaction rating: Study Supported

In one study, 30% of patients taking metformin developed a decreased ability to absorb vitamin B12. Supplementation with the affected nutrient may be necessary. (1)

These drugs include metformin


  1. View Abstract: Adams JF, et al. Malabsorption of Vitamin B12 and Intrinsic Factor Secretion During Biguanide Therapy. Diabetologia. Jan1983;24(1):16-18.