Dizziness after taking a shower usually has the following four factors: First, after taking a shower, the head capillaries expand, and the hot environment will lead to a transient cerebral artery blood supply deficiency, especially the internal carotid artery system and the vertebral basilar artery system blood supply deficiency is particularly significant, so it will cause dizziness. Second, the bath time is too long will be excessive consumption of glycogen in the body, start glycolysis pathway, which will greatly reduce the body’s blood sugar, when the blood sugar is too low will cause dizziness, headache, and even a transient hypoglycemic reaction. Thirdly, if the capillaries are strongly dilated during bathing, it will cause lack of oxygen to the brain, and then, if the oxygen saturation of arterial blood decreases too fast, the partial pressure of oxygen drops significantly, which will also cause lack of oxygen and induce dizziness and lightheadedness. Fourth, such as coronary artery atherosclerosis heart disease bath time is too long, will trigger the head vascular blood supply and heart blood supply insufficiency will also cause dizziness.