Patients with a history of hypersensitivity reaction to metformin or any excipients.
Patients with acute catabolic states, infection, trauma, which all should be treated with insulin.
Decreased kidney function in renal disease or renal dysfunction (serum creatinine greater than or equal to 1.5 mg/dL in males, or greater than or equal to 1.4 mg/dL in females) which may also result from conditions such as cardiovascular collapse, acute myocardial infarction, and septicemia.
Severe renal impairment (eGFR below 30 mL/minute/1.73 m2) (see Precautions).
Patients with acute or chronic metabolic acidosis including diabetic ketoacidosis.
Severe hepatic disease, severe cardiovascular disease, severe respiratory disease with hypoxaemia.
Congestive heart failure, cardiovascular collapse, acute myocardial infarction.
Chronic hypoxic lung disease.
Severe infection, septicemia.
In acute symptoms of metabolic decompensation, for instance in cases of infection or gangrene.
In pregnant, patients who are always treated with insulin.
Metformin should be temporarily withheld in patients undergoing radiologic studies involving the parenteral administration of iodinated contrast materials because use of such products may result in acute alteration of renal function.
Gangrene, alcoholism, malnutrition.