Low blood pressure, i.e. diastolic blood pressure of 90mmHg, for a long period of time may cause dizziness, headache, fatigue and other symptoms, and may cause damage to target organs in the body. Grade 1 hypertension refers to blood pressure in 140~159 and/or 90~99mmHg, diastolic pressure 90mmHg already belongs to the category of grade 1 hypertension, at this time, the rise in blood pressure is not obvious, the early may not appear symptoms and harm, in the long run, may appear dizziness, headache, fatigue and other symptoms, and even cause target organs in the body, such as the heart, brain, kidneys and so on. When diastolic blood pressure is 90mmHg, you should first change your lifestyle to control your blood pressure, such as low-salt and low-fat diet, appropriate exercise, and keep a good mindset, etc. If your blood pressure can not be effectively controlled, or even if your blood pressure gradually increases, you can consider using antihypertensive medication to control your blood pressure, such as captopril, amlodipine, etc. Please follow your doctor’s instructions when taking medication. Please follow your doctor’s instructions. Long-term diastolic blood pressure of 90mmHg should be examined in the hospital in time and treated according to the doctor’s instructions.