There is no such thing as how much difference in blood pressure between morning and afternoon is normal; the fact that the patient’s blood pressure fluctuates within the normal range indicates that it is normal.
A normal patient’s blood pressure is 90-120 mm Hg systolic and 60-80 mm Hg diastolic. The high values of normal blood pressure are 120-139 mm Hg systolic and/or 80-89 mm Hg diastolic.
Normal blood pressure has a spoon-shaped rhythm, with two peaks in a day: 8:00-10:00 a.m. and 4:00-8:00 p.m. The peak of blood pressure in the morning is slightly greater than that in the afternoon, and it gradually decreases in the evening, with a trough in the early morning.
If the systolic blood pressure is greater than or equal to 140 mmHg and/or diastolic blood pressure is greater than or equal to 90 mmHg in three measurements taken on non-simultaneous days, hypertension is considered.
If blood pressure fluctuation with obvious discomfort occurs, you should go to the hospital for treatment.