Patients who have been lying down for a long time may get dizzy when they get up, usually due to the following factors: 1. The most common factor is postural hypotension, which is common in the elderly and occurs when there is a change in position due to poor blood pressure regulation mechanism and atherosclerosis. 2. For patients with otoliths, dizziness may also occur after a change in position, accompanied by 3. Endocrine metabolic diseases, such as those with a history of diabetes mellitus, may cause dizziness after standing up if there is a hypoglycemic reaction. 4. If patients have long-term chronic heart insufficiency, especially those with heart failure, they may also experience dizziness after standing up after lying down for a long time.