Patient: I am 65 years old and was just recently diagnosed with type 2 diabetes. My doctor prescribed me metformin to control my blood sugar, but some diabetic patients told me that metformin will hurt my liver and kidneys if I take it for a long time, so it is better not to take it and switch to other glucose-lowering drugs. Is it suitable for diabetic patients to take it? Hospital endocrinology metabolism department chief physician: many diabetic patients often have concerns about the use of metformin, that metformin will “hurt the liver”, “kidney”, so some patients often stop using it on their own. In fact, as a 50-year-old drug in clinical use, metformin plays a very important role in the treatment of diabetes, and many diabetes guidelines have made metformin the first-line drug throughout the treatment of diabetes. Moreover, with the in-depth research, it is found that metformin not only has hypoglycemic effects, but also has certain effects in lipid-lowering, anticoagulation, cardiovascular protection and anti-tumor. Currently, metformin is also the only oral hypoglycemic agent approved by the U.S. Food and Drug Administration (FDA) for use in children with type 2 diabetes. In addition, metformin alone generally does not cause hypoglycemia, so the drug also has a good safety profile. Many diabetic patients say that metformin can “hurt the liver” and “hurt the kidneys”, but in fact, they are confused about the precautions of metformin use. Metformin is mainly excreted in its original form through the kidneys, and its main side effect is the possibility of lactic acidosis, but if you master the contraindications of metformin, lactic acidosis is rare. Clinically, metformin is generally not suitable for use if the following conditions exist: first, when liver or kidney insufficiency, mainly because liver and kidney insufficiency may induce lactic acidosis; second, patients with serious heart and lung diseases, due to the presence of hypoxia may also easily induce lactic acidosis; third, 48 hours before and after the use of iodine contrast agent; fourth, when acute complications of diabetes such as ketoacidosis occur. It can be seen that metformin itself does not “harm the liver” and “harm the kidneys”, but should be used with caution or discontinued only when the liver and kidney function has been damaged.