Metformin Causes Vitamin B12 Deficiency

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Suresh Kanna S.
Srinivasa Rao Gopisetty
Kavuru Naga Siri
Nitharsha Prakash
Goutham Kumar A. P.


Metformin is a first drug of choice of oral diabetic drug for hyperglycemia in diabetes is generally regarded as having few cause vitamin B12deficiency.Ithasbeenreportedthatanaverageof6%to30%ofpatients could show vitamin B12 deficiency due to metformin use. The 2017 American Diabetes Association treatment guidelines now recommend regular monitoring of vitamin B 12 levels in patients with diabetes taking metformin. Metforminal so causes VitB12deficiencywhichisarareside effect of prolonged metformin therapy. Many studies showed the inverse relationship between the prolonged usage and dosage of metformin usage and B12 serum levels.

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Kanna S., S. ., Rao Gopisetty, S. ., Naga Siri, K. ., Prakash, N. ., & A. P., G. K. . (2023). Metformin Causes Vitamin B12 Deficiency. Journal of Coastal Life Medicine, 11(1), 239–243. Retrieved from


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