TY - JOUR T1 - Levels of evidence needed for changing indications, contraindications, and food and drug administration labeling: The case of metformin—reply AU - Roussel R, Bhatt DL, Steg P, et al Y1 - 2011/06/13 N1 - 10.1001/archinternmed.2011.225 JO - Archives of Internal Medicine SP - 1042 EP - 1043 VL - 171 IS - 11 N2 - We are aware of previous well-conducted observational studies by Eurich and others evaluating the safety of metformin in patients with HF patients, and we believe that the changes in product monographs of metformin, down-toning the contraindication of the drug in diabetic patients with stable HF are welcome. Our results extend the basis of these labeling changes, but they also provide indications that other contraindications, such as renal insufficiency, may not be as justified as previously believed. Moreover, the issue is not only to mitigate contraindications, but possibly to switch some of them to indications—a tempting prospect for subjects with HF and diabetes, for example, that cannot be achieved without the highest level of evidence. SN - 0003-9926 M3 - doi: 10.1001/archinternmed.2011.225 UR - http://dx.doi.org/10.1001/archinternmed.2011.225 ER -