Most people’s blood pressure fluctuates in a circadian rhythm, i.e., it starts to rise in the morning and is lower at night after going to sleep. Generally, there are two peak periods in a day, namely 6-10 a.m. and 4-8 p.m. (the morning “peak” is higher than the afternoon “peak”), and the curve is “spoon shaped”. Therefore, it is necessary to monitor blood pressure at least twice a day. However, in patients with hypertension, the pattern of blood pressure fluctuation is different from that of normal people, showing that the blood pressure is higher than normal people after waking up in the morning and is still high at night, so the number of times the blood pressure is monitored daily should be higher. According to the different duration of action of antihypertensive drugs, they can be clinically classified as long-acting, medium-acting and short-acting. The long-acting antihypertensive effect lasts for a long time, lasting about 24 hours, and is generally available once a day, while the short-acting duration is short, and the effect disappears 6 to 8 hours after taking the drug, requiring three times a day; the medium-acting effect lasts about 12 hours, requiring twice a day. If the blood pressure is high in the morning after waking up, excluding the sleep factor, you should monitor the blood pressure before going to bed, if the blood pressure is also high before going to bed, it indicates that the amount of antihypertensive drugs is insufficient or the action time is short, you can increase the amount of antihypertensive drugs or use long-acting antihypertensive drugs. If the blood pressure is not high before going to bed, but suddenly rises in the morning, you should take antihypertensive drugs earlier when you first wake up or even at 3 to 5 in the morning. 2, short-acting preparations generally reach the maximum degree of pressure reduction 2 hours after taking the drug, medium-acting and long-acting preparations of antihypertensive effect peak in 2 to 4, 3 to 6 hours after taking the drug, so 2 to 6 hours after taking antihypertensive drugs to measure blood pressure, can reflect the maximum antihypertensive effect of drugs. To understand the fluctuation pattern of your blood pressure, it is helpful to guide the doctor to adjust the dose and time of medication in time, in order to better and more stable control of blood pressure.