High blood pressure when waking up from a nap may be due to the lack of airway clearance during sleep, which causes carbon dioxide retention and sympathetic nerve excitation, thus causing blood pressure to rise, and it may also be caused by low concentration of antihypertensive drugs in the body and temperature changes. 1. The situation of high blood pressure when waking up from a nap is called sleep hypertension, which is a special type of hypertension, manifested as elevated blood pressure during sleep or after waking up from sleep. The pathogenesis is mainly due to poor respiration during sleep, shallow and slow respiration, decreased oxygen saturation, increased carbon dioxide concentration caused by sympathetic nerve excitation, which leads to increased blood pressure. 2. Patients who have high blood pressure when they get up from nap may also have lower concentration of drugs in their body, which can’t control their blood pressure. If the patient is taking a short-acting antihypertensive drug, after taking it in the morning, the drug is not used at noon, which can lead to an increase in blood pressure. Taking is a long-acting antihypertensive drug, but in the evening before bedtime, the midday effect of the drug is weakened, can also lead to increased blood pressure. 3. Napping up high blood pressure may also be caused by temperature changes, low temperatures in the morning and evening, high temperatures at noon, temperature changes in the sympathetic nerve excitation, can make the blood pressure rise. Napping up high blood pressure patients are recommended to use medication according to the guidance of the doctor, do not stop taking medication, so as not to affect the health of the body.