Sudden dizziness and rapid heartbeat are both physiological and disease factors, physiological factors are seen in mental stress, rest is not good. Disease factors can be seen in hypoglycemia, arrhythmia, hypertension and so on. 1. Physiological factors: if the body is overworked, and work and study pressure, and usually drink strong tea and coffee before going to bed, may cause rapid heartbeat and dizziness, which belongs to the normal physiological response, do not need special treatment, you can adjust the appropriate sleep time, do not drink anything before going to bed. 2. Pathological factors: (1) Hypoglycemia: hypoglycemia may be caused by insufficient intake of sugar and insufficient production, or it is caused by excessive consumption of sugar in the body, which will lead to hunger, pallor, sweating and palpitations, accompanied by symptoms of rapid heartbeat and dizziness, which can be treated with oral glucose injection. (2) Hypertension: When the blood pressure rises, there will be sudden dizziness, accompanied by symptoms of myocardial ischemia, panic, palpitations, rapid heartbeat, it is recommended that the patient can take oral perindopril or nifedipine controlled-release tablets to control the blood pressure. (3) Arrhythmia: Supraventricular tachycardia or atrial fibrillation can also cause dizziness and rapid heartbeat, etc. Improvement of electrocardiogram will help to clarify whether arrhythmia is occurring and identify the type of arrhythmia. The causes of sudden dizziness and rapid heartbeat are very complex, and it is recommended to consult a doctor for timely and systematic treatment under the guidance of a doctor.