International Journal of Drug Delivery Technology
Volume 16, Issue 1, 2026

Effect of Cobalamin Levels in Patients with T2DM Undergoing Metformin Therapy

Dr. V. Pavithra, Dr. V. S. Kalaiselvi*, Dr. B. Shanthi, Dr. K. Sumathi

Post Graduate, Department of Biochemistry, Sree Balaji Medical College & Hospital, BIHER

M.D. Professor, Department of Biochemistry, Sree Balaji Medical College & Hospital, BIHER (*Corresponding author)

M.D. Professor, Department of Biochemistry, Sree Balaji Medical College & Hospital, BIHER

M.D. Professor, Department of Biochemistry, Sree Balaji Medical College & Hospital, BIHER

Mailing address: Department of Biochemistry, Sree Balaji Medical College & Hospital, BIHER, #7, Works Road, New Colony, Chrompet, Chennai-600044. INDIA.

Received: 5th Jan, 2026; Revised: 25th Jan 2026; Accepted: 20th Feb, 2026; Available Online: 10th Mar, 2026

ABSTRACT

Low vitamin B12 concentrations are being documented more often in people living with T2DM. Metformin, still the first choice for glycaemic control, appears to be a major contributor to this trend. Although the link between metformin use and reduced Cobalamin levels is well supported, the extent to which dose, duration of therapy and individual patient factors shape this relationship varies across studies. Interpretation is made more difficult by the absence of a single, universally accepted cutoff for defining deficiency, which leads to wide differences in reported prevalence. Long-standing Cobalamin deficiency can result in neurological and haematological problems, making periodic evaluation of vitamin B12 status important for those at higher risk. Individuals following vegan diets while using metformin are particularly susceptible because their dietary intake of Cobalamin is limited. Lifestyle approaches that help maintain metabolic balance may also reduce the chance of developing nutritional deficiencies during extended treatment.

Keywords: Metformin, blood glucose monitoring, Vitamin B12, Neurological symptoms.

How to cite this article: Pavithra V, Kalaiselvi V S, Shanthi B, Sumathi K. Effect of Cobalamin Levels in Patients with T2DM Undergoing Metformin Therapy. Int J Drug Deliv Technol. 2026;16(1): 754-758. DOI: 10.25258/ijddt.16.1.80.

Source of support: Nil.

Conflict of interest: None