Place of metformin in modern clinical guidelines for the treatment of type 2 diabetes mellitus

Diabetes mellitus is one of the most common endocrine diseases. Type 2 diabetes mellitus is associated with high cardiovascular morbidity and mortality and is a leading cause of chronic kidney disease and end-stage kidney disease. To date, for the treatment of patients with type 2 diabetes, hypoglycemic drugs are used that affect different parts of the pathogenesis. Metformin is a biguanide that is used in the treatment of type 2 diabetes mellitus; it is effective as monotherapy and in combination with other glucose-lowering medications. In addition to the treatment of diabetes mellitus, metformin is recommended and widely used for the treatment of prediabetes. Metformin is generally well-tolerated with minimal side effects and is affordable. Metformin is very effective in HbA1c lowering associated with some weight loss, but does not increase risk for hypoglycemia. With the use of metformin in monotherapy, the decrease in HbA1c levels is 1–2%. Despite the appearance in practice of a fairly large number of new, effective glucose-lowering drugs, metformin is still the drug of choice in many cases. And most diabetic associations recommend metformin as a first-line drug. Metformin has demonstrated many positive effects in observational studies in patients with CAD, heart failure, and chronic kidney disease. This review presents data on the efficacy and, pleiotropic effects of metformin. Possible adverse events are also discussed, including the risk of low level and deficiency of vitamin B12, gastrointestinal tract adverse events.

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