Excessive blood loss can cause dizziness. When a person loses too much blood, there will be insufficient blood volume, resulting in insufficient blood volume in all organs of the body. Because insufficient blood volume leads to insufficient oxygen carried by the blood, when the brain tissue is deprived of blood and oxygen, the symptoms of brain function deficiency will occur. For example, after severe ischemia and hypoxia in the cerebral hemispheres, the patient will experience weakness in the limbs. If the brainstem and cerebellum are ischemic, the patient will experience dizziness, numbness of the limbs, and in severe cases, nausea and vomiting. Therefore, excessive blood loss will cause dizziness. Patients are advised to drink more water and replenish blood volume, and if necessary, blood transfusion therapy can be considered.