Context

Metformin is the only oral antidiabetic drug shown to improve cardiovascular outcomes. A common clinical conundrum facing practitioners while using metformin is the potential risk of lactic acidosis (LA) which has a high mortality rate. Hence, according to the product information, metformin has several contraindications including renal impairment. However, recent studies have questioned some of these contraindications. In particular it has been suggested that the US Food and Drug Administration (FDA) recommendation to prescribe metformin based on serum creatinine (SCr) is overly conservative and may preclude many patients from taking metformin.1 The study by Tout et al investigated the impact of prescribing metformin based on SCr versus the estimated glomerular filtration rate (eGFR) …