1-Ebadi AR ,Golbidi S ,Taghadosi M ,Vakili Z, Arbab B, Sarboloki SH, et. al. Effect of metformin in serum level vitamin B12 and folic acid in patients with type 2 diabetes mellitus. Journal of Ardebil medical sciences university 2009;8(4):403-7.
2-Jager J, Kooy A, Lehert P, Wulffele MG, Kolk J, Bets D, et.al. Long term treatment with metformin in patients with type 2 diabetes and risk of vitamin B12 deficiency:randomised placebo controlled trial. BMJ 2010; 340:c2181.
3-Palomba P, Falbo A, Giallauria F, Russo T, Tolino A, Zullo F, et.al. Effects of metformin with or without supplementation with folate on homocysteine levels and vascular endothelium of women with polycystic ovary syndrome.Diabetes Care 2010; 33(2):246-51.
4-Shtaynberg N, Singh M, Sohn P, Goldman M, Cohen N. Methylmalonic acid as an indicator of vitamin B12 deficiency in patients on metformin. J of diabetes mellitus 2.01 (2012): 72.
5-Kos E, Liszek MJ, Emanuele MA, Durazo-Arvizu R, Camacho P. Effect of metformin therapy on vitamin D and vitamin B12 levels in patients with type 2 diabetes mellitus. Endocr Pract 2012; 18(2):179-84.
7-Pflipsen M, Oh RC, Saguil A, Seehusen DA, Seaquist D, Topolski R. The Prevalence of Vitamin B12 Deficiency in Patients with Type 2 Diabetes: A Cross-Sectional Study. The Journal of the American Board of Family Medicine 2009; 22 (5): 528-34 .
9-Tomkin GH, Hadden DR, Weaver JA, Montgomery DAD.Vitamin-B12 Status of Patients on Long-term Metformin Therapy. Br Med J 1971 ; 2(5763): 685–7.
10-Tomkin GH. Malabsorption of vitamin B12 in diabetic patients treated with Phenformin: A comparision with Metformin. Br Med J 1973; 3(5882): 673–5.
11-Wullfele MG, Kooy A, Lehert P, Bets D, OgteropJC,BorgerVA, et. al. Metabolic evidence that deficiencies of vit B12, folate and vitamin B6 occur. J Intern Med 2003; 254(5): 455-63.
13-Delva M, Dianne B. Vitamin B12 replacement or not. Canadian family physician 1997; 43: 917.
14-Sahin M, Tutuncu NB, Ertugrul D, Tanaci N, Guvener ND. Effect of metformin or rosiglitazone on serum concentrations of homocysteine, folate, and vitamin B12 in patients with type 2 diabetes mellitus. J Diabetes Complications 2007;21: 118-23.
15-Hermann L, Nilsson B ,Wettre S. Vitamin B12 status of patients treated with metformin: a cross-sectional cohort study, Department of Clinical Chemistry, Uddevalla Hospital, Sweden. British Journal of Diabetes & Vascular Disease 2004; 4 ( 6): 401-6.
16-Nervo M, Lubini A, RaimundoVF, Faulhaber GAM, Leite C, FischerLM, et. al.Vitamin B12 in metformin-treated diabetic patients: a cross-sectional study in Brazil. Rev. Assoc. Med. Bras 2011; 57(1): 46-9 .
17-
Wile DJ,
Toth C. Association of metformin, elevated homocysteine and methylmalonic acid levels, and clinically worsened diabetic peripheral neuropathy . Diabetes Care 33.1 (2010): 156-161.
18-
Jager JD,
Kooy A,
Lehert P. Long term treatment with metformin in patients with type 2 diabetes and risk of vitamin B12 deficiency: randomised placebo controlled trial .BMJ 2010; 340:c2181.
20-Sato Y, Ouchi K, Funase Y, Yamauchi K, Aizawa T.Relationship between metformin use, vitamin B12 deficiency, hyperhomocysteeinemia and vascular complications in patients with type 2 diabetes.Endocrine Journal 60.12 (2013): 1275-1280.
21-Liu KW, Dai DLK, Ho W, Lau E, Woo J.Metformin-associated vitamin B12 deficiency in the elderly. Asian J Gerontol Geriatr 2011;6:82-7.