The timing of taking glucose-lowering drugs is related to the type of glucose-lowering drugs and their mechanism of action, and cannot be generalized. For biguanides, sulfonylureas, glinides and dipeptidyl peptidase-4 inhibitors, they should be taken before meals; for glycosidase inhibitors, they should be chewed at the first bite of food; for thiazolidinediones and SGLT-2 inhibitors, there is no fixed time for taking them. There are many types of glucose-lowering drugs, and different glucose-lowering drugs have different mechanisms of action and different methods of administration. Metformin-type hypoglycemic drugs have stimulating effect on the gastrointestinal tract, and the effect on the gastrointestinal tract can be weakened by taking them after meals; sulfonylurea and glargine type hypoglycemic drugs are pro-secretory agents, which promote the secretion of insulin and can act on the rise of blood sugar after meals when taken before meals; dipeptidyl peptidase-4 inhibitors hypoglycemic drugs, which generally need to be taken before breakfast; glycosidase inhibitors can lower blood sugar after meals and need to be taken with carbohydrates; thiazolidinediones and SGLT-2 inhibitors can be taken once a day. Patients with diabetes should follow medical advice while taking glucose-lowering drugs, and should not make decisions without permission.