If hypertensive patients suddenly appear low blood pressure, mostly seen in the following cases: 1, may be related to the climate, the normal human body in cold weather, blood vessels are contracted, often hypertensive patients once to the autumn and winter seasons or winter and spring, blood pressure will rise more obvious, to the summer temperature is higher, vascular expansion, blood pressure may be lower than before, that is, the weather is hot caused by vasodilation caused by low blood pressure; 2, some patients appear High blood pressure, high blood pressure suddenly low, need to consider may patients on the type of medication or dose is not clear, so family members should be careful whether the patient’s dose and type of medication is correct, including the need to pay attention to whether the drug is the same brand or the same manufacturer, may have an impact on the patient’s blood pressure; 3, if the above circumstances are ruled out, blood pressure suddenly appear lower, it is necessary to clarify whether the patient has symptoms. If the patient has a combination of dizziness, headache, loss of appetite or significant weight loss, it is necessary to pay attention to it and go to the hospital in time to clarify the cause of the sudden decrease in blood pressure.