Insufficient blood supply of vertebral basilar artery is a diagnostic name commonly used in the past, which has been changed to posterior circulation ischemia. The most common clinical manifestations of this disease are dizziness, unsteady walking and swaying, which are caused by ischemia and hypoxia of the brain, especially the cerebellum and brain stem. Treatment should be based on improving blood supply, and commonly used drugs are as follows: i. Aspirin, which is mainly used to resist platelet aggregation, reduce blood viscosity, and prevent thrombosis; ii. Calcium atorvastatin, which is used to stabilize atherosclerotic plaques, prevent further aggravation of vascular stenosis and occlusion, and prevent plaque dislodgement from causing secondary cerebral infarction; iii. Sodium beclomethasone tablets, which are mainly used to dilate blood vessels, improve Microcirculation, so that the blood supply to the brain increases; four, Nicergoline tablets, the main role is to increase the blood supply and oxygen supply to brain cells to improve brain metabolism.