In the treatment of diabetes, a lot of time simply an oral hypoglycemic drug application can not effectively control the stability of blood glucose to the standard, often need to combine drugs, so that the joint application of drug programs have what advantages, and can improve the effect of lowering glucose as well as to achieve the standard rate, we say the following this problem. 1, sulfonylurea and biguanide combination: sugar effect is good and low cost, for fasting and postprandial blood glucose are relatively strong. 2, sulfonylureas and alpha-glucosidase inhibitors: suitable for patients who can not control postprandial blood glucose with sulfonylureas alone, the effect of postprandial blood glucose is relatively good. 3, Biguanide and thiazolidinediones combination: this combination is more suitable for hyperinsulinemia, that is to say, high insulin levels, blood sugar is not normal, there is obvious insulin resistance patients. 4, Biguanides and DPP-4 inhibitors combination: not only has a good effect of lowering sugar and does not cause hypoglycemia, does not increase body weight. Of course, the combination of drugs is also a good idea, generally two is more appropriate, more than three is appropriate, if the combination of too many kinds of drugs, or the dose of drugs is too large, it will produce obvious side effects, the damage to the liver and kidneys is also a problem that needs attention.