A comparative study of efficacy and safety of anti-oxidants as an add-on therapy to metformin on glycemic parameters in newly diagnosed type 2 diabetes mellitus patients at a tertiary care hospital


  • Yashaswini P. Department of Pharmacology, Sapthagiri Institute of Medical Sciences and Research Centre, Bengaluru, Karnataka, India
  • Geetha A. Department of Pharmacology, Bangalore Medical College and Research Institute, Bengaluru, Karnataka, India
  • Ravi K. Department of Medicine, Bangalore Medical College and Research Institute, Bengaluru, Karnataka, India




Diabetes mellitus, Oxidative stress, Metformin, Vitamin C, Vitamin E


Background: Oxidative stress plays major role in diabetes mellitus (DM), abnormal high free radicals decline antioxidant defence mechanism can lead to damage of cellular organelles and enzymes, increased lipid peroxidation and insulin resistance leads to development of complications. Supplementation of antioxidants protects free radical induced damage and further complications. The objective was to evaluate the efficacy and safety of metformin versus metformin with vitamin C and E on glycaemic parameters in newly diagnosed type 2 diabetes mellitus (T2DM).

Methods: 60 newly diagnosed T2DM patients were randomized into two groups of 30 in each to receive metformin (500 mg BD) alone in group A versus metformin (500 mg BD)+vitamin C (500 mg OD)+vitamin E (400 mg OD) in group B for 12 weeks. Efficacy was measured by improvement in glycaemic (FBS fasting blood sugar, PPBS postprandial blood sugar and HbA1c glycosylated haemoglobin) parameters at week 4, 8 and 12 from baseline. Safety was assessed by monitoring treatment emergent adverse effects.

Results: The baseline characteristics were comparable between the two groups. There was a significant reduction of glycaemic parameters seen in both the groups from baseline to week 12 (p<0.001) but the difference was not statistically significant between the two groups (p>0.05). No significant adverse effects were noted.

Conclusions: Both the groups are effective in improving glycaemic indices and supplementation of vitamins along with metformin as compared to metformin alone with no significant adverse effect. Hence, daily consumption of vitamins may be beneficial in decreasing blood glucose in patients with T2DM and thus reducing the risk of complications.


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How to Cite

P., Y., A., G., & K., R. (2021). A comparative study of efficacy and safety of anti-oxidants as an add-on therapy to metformin on glycemic parameters in newly diagnosed type 2 diabetes mellitus patients at a tertiary care hospital. International Journal of Basic & Clinical Pharmacology, 10(8), 925–931. https://doi.org/10.18203/2319-2003.ijbcp20212919



Original Research Articles