Dizziness and weakness of limbs may be caused by hypertension, cerebral arteriosclerosis and upper respiratory tract infection. 1. Hypertension: Due to the abnormally high blood pressure, patients with hypertension may suffer from systolic-diastolic dysfunction of cerebral blood vessels, which is manifested as dizziness and swelling of the brain and weakness of the limbs. 2. cerebral arteriosclerosis: mostly occurring in the elderly group, due to long-term arteriosclerosis makes the cerebral vascular resistance index abnormally high, the blood flow rate slows down, and the brain tissue suffers from ischemia and hypoxia, which may manifest as dizziness, lack of clarity of the mind, and accompanied by physical weakness. 3. Upper respiratory tract infection: If upper respiratory tract infection occurs, the inflammatory factors released by bacteria and viruses may lead to vasodilatation, resulting in dizziness, brain swelling and body weakness. Dizziness and weakness may also be caused by other diseases, such as cerebral hemorrhage and cerebral infarction. It is recommended to seek prompt medical attention to identify the causative factors and follow the doctor’s instructions to avoid accidents.