Sleepiness at 3 or 4 o’clock every afternoon, 1. may be caused by elevated blood pressure. Blood pressure should be monitored, and if it is high, blood pressure can be lowered for treatment. Severe hypertension may cause ischemia and hypoxia in the brain, and patients may experience headache, dizziness, lightheadedness, and also drowsiness, and the main blood pressure lowering treatment, commonly used drugs are amlodipine and irbesartan. The human blood pressure has 2 peak time periods every day, mainly at 8-10 a.m. and 4-6 p.m. 2, may also be caused by lack of sleep, people normally need a lunch break, if not at noon, may be 3, 4 o’clock in the afternoon sleepy. In addition, it may be caused by other diseases, such as intracranial organic lesions, if necessary, should check the cranial CT or cranial MRI, in order to clarify the diagnosis.