[Lactic acidosis in diabetic patient treated with metformin]

We present a case of metabolic acidosis in a man, recently diagnosed with type 2 diabetes mellitus under treatment with metformin. Metformin (along with Fenformin and Butformin) is an oral antihyperglycemic agent belonging to the biguanide group employed in the treatment of non insulin dependent diabetes (NIDDM). Its main use is in association with other oral agents in obese diabetic patients with difficult metabolic control. In some of these patients, clearly beneficial developed lactic acidosis, specially in those who have predisposing factors (respiratory failure, liver disease or cardiovascular disease) and/or those who require high doses. For this reason we describe its pharmacokinetics, therapeutic indications and its correct use in this type of diabetic patient.