Use is not advised in patients w/ type 1 DM; polycystic kidney disease or those who need or have recently received immunosuppressive therapy for renal disease; eGFR <45 mL/min/1.73 m
2; liver impairment. Discontinue treatment in patients w/ history of liver disease, alcoholism, or heart failure, & those who will receive intra-arterial iodinated contrast at time of or before an iodinated contrast imaging procedure; re-evaluate eGFR 48 hr following imaging procedure, & resume therapy if renal function is stable. Avoid treatment for at least 3 days before undergoing major surgery or extended fasting procedures; start treatment once patient is clinically stable & has resumed oral intake. Post-marketing cases of metformin-associated lactic acidosis, including fatal cases. Consider ketone monitoring in patients at risk for ketoacidosis. Assess for ketoacidosis regardless of presenting blood glucose levels & discontinue use if ketoacidosis is suspected; monitor for resolution of ketoacidosis before restarting therapy. Assess & correct vol status in elderly, patients w/ renal impairment or low systolic BP, & those on diuretics before initiating treatment; monitor for signs & symptoms of vol depletion during therapy. Evaluate for signs & symptoms of UTI & treat promptly, if indicated. Consider lower dose of concomitant insulin or insulin secretagogue. Institute prompt treatment if necrotizing fasciitis of the perineum (Fournier's gangrene) is suspected. May lower vit B
12 levels; measure hematological parameters annually. Monitor for genital mycotic infections & treat if indicated. May lead to +ve urine glucose tests & interference w/ 1,5-anhydroglucitol (1,5-AG) assay. Use is not advised during 2nd & 3rd trimesters of pregnancy & during nursing. Possibility of unwanted pregnancy in premenopausal women. Safety & efficacy in childn <10 yr have not been proven. Frequently evaluate renal function in the elderly.