Metformin is mainly used for the treatment of type 2 diabetes mellitus, whether patients with nephritis can take metformin needs to be determined according to renal function, patients with mild to moderate impairment of renal function can take but should reduce the dose, severe renal failure is prohibited this drug, the occurrence of dehydration, severe infections, shock, and other acute conditions that may affect the renal function is prohibited when this drug. Metformin belongs to the biguanide class of hypoglycemic drugs, can reduce hepatic glucose synthesis, inhibit intestinal absorption of glucose, mainly used in the treatment of type 2 diabetes mellitus. Metformin is excreted by the kidneys, and renal function should be examined before using the drug, and regularly reviewed during the drug. Nephritis patients need to assess renal function before using the drug, people with normal renal function can use the drug, patients with mild to moderate impairment of renal function can also be taken but the dose should be reduced, severe renal failure is prohibited this drug, the occurrence of dehydration, severe infections, shock, and other acute conditions that may affect renal function is prohibited this drug. In addition, it is contraindicated in patients with serious complications, pregnant women, lactation, alcoholism and so on. Common adverse reactions to Metformin include gastrointestinal reactions, skin irritation and lactic acidosis. Metformin should be used in strict compliance with medical advice.