Hypersensitivity reactions; promptly stop medication & institute appropriate monitoring & treatment. Lactic acidosis. Discontinue if pancreatitis is suspected. Discontinue therapy if severe & disabling arthralgia or bullous pemphigoid has been reported. Consider risks & benefits in patients who have known risk factors for heart failure. Risk of hypoglycemia when used in combination w/ insulin &/or insulin secretagogue. Discontinue at time of, or prior to, iodinated contrast imaging procedures. Avoid use in patients w/ hepatic impairment. Not recommended in patients w/ eGFR between 30 & <45 mL/min/1.73 m
2. Assess renal function w/ eGFR prior to initiation, & at least annually. Acute renal failure sometimes requiring dialysis. Potential unintended pregnancy in premenopausal females. Metformin: May lower vit B levels. Measure hematologic parameters annually & vit B at 2-3 yr intervals.