Hypersensitivity to metformin hydrochloride or to any of the excipients.
Diabetic ketoacidosis, diabetic pre-coma.
Renal failure or renal dysfunction (creatinine clearance < 60ml/min).
Acute conditions with the potential to alter renal function such as: dehydration, severe infection, shock, intravascular administration of iodinated contrast agents.
Acute or chronic disease which may cause tissue hypoxia such as: cardiac or respiratory failure, recent myocardial infarction, shock.
Hepatic insufficiency, acute alcohol intoxication, alcoholism.
Severely reduced kidney function (GFR <30 mL/min).
Any type of acute metabolic acidosis (such as lactic acidosis, diabetic ketoacidosis)