Polarized light micrograph of Metformin crystals. Metformin is a biguanide antihyperglycemic agent. It is the first-line drug of choice for the treatment of non-insulin-dependent diabetes mellitus (NIDDM), diabetes mellitus type 2. Its metabolic effects, including the inhibition of hepatic gluconeogenesis, are mediated by the activation of the enzyme LKB1-AMPK (AMP-activated protein kinase) pathway. It appears to be involved in the antiproliferative and proapoptotic actions in cancer cell lines. It is also used in the treatment of polycystic ovary syndrome and gestational diabetes. It helps lowering LDL cholesterol and triglyceride levels. Field of view size: 0.744 x 1.116 mm (0.029 x 0.044 in)