Metformin: Past, Present, and Future

This review provides the most recent update of metformin, a biguanide oral antihyperglycemic drug used as a first-line treatment in type 2 diabetes mellitus.

Metformin continues to dominate in the world of antidiabetics, and its use will continue to rise because of its high efficiency and easy availability. Apart from type 2 diabetes, research is exploring its potential in other conditions such as cancer, memory loss, bone disorders, immunological diseases, and aging. Metformin is the most prescribed oral antidiabetic worldwide. It has been in practical use for the last six decades and continues to be the preferred drug for newly diagnosed type 2 diabetes mellitus. It reduces glucose levels by decreasing hepatic glucose production, reducing intestinal glucose absorption, and increasing insulin sensitivity. It can be used as monotherapy or combined with other antidiabetics like sulfonylureas, DPP-4 inhibitors, SGLT-2 inhibitors, or insulin, improving its efficacy. Metformin can be used once or twice daily, depending on requirements. Prolonged usage of metformin may lead to abdominal discomfort, deficiency of Vitamin B12, or lactic acidosis. It should be used carefully in patients with renal impairment. Recent studies have explored additional benefits of metformin in polycystic ovarian disease, gestational diabetes mellitus, cognitive disorders, and immunological diseases. However, more extensive studies are needed to confirm these additional benefits.