Diabetic ketoacidosis, diabetic pre-coma; moderate & severe renal impairment (CrCl <60 mL/min). Acute conditions potentially alter renal function (eg, dehydration, severe infection, shock, IV iodinated contrasts). Acute or chronic disease may cause tissue hypoxia (eg, cardiac or respiratory failure). Hepatic impairment; acute alcohol intoxication, alcoholism. Lactation.