There is no such thing as which is the most effective Acarbose or Metformin. Acarbose and metformin belong to different kinds of hypoglycemic drugs, with different hypoglycemic mechanisms, and cannot be generalized. 1. Acarbose: belongs to glucosidase inhibitors, through the inhibition of small intestinal wall cells to inhibit the absorption of sugar to lower sugar, can inhibit the activity of maltose, isomaltose, glucoamylase, sucrase, so that glucose from carbohydrates absorption and degradation of slow, mainly to reduce postprandial blood glucose. Adverse reactions include bloating, diarrhea, nausea, and vomiting. Allergic to the product, severe renal impairment and other people are prohibited. 2. Metformin: It belongs to the class of biguanide drugs, through inhibiting the output of hepatic glycogen, increasing the sensitivity of peripheral tissues to insulin, and playing the role of lowering blood glucose. Adverse reactions include digestive system symptoms, skin allergies and so on. It is forbidden for people who are allergic to this drug, severe liver and kidney insufficiency, serious infection, acute alcoholism and so on. It is recommended that patients who need to lower their blood sugar go to a regular hospital for medical consultation, and choose a glucose-lowering drug under the guidance of a doctor according to the specific situation, do not take the drug on your own.