Ask the doctor: Erratic blood pressure readings
Q. I check my blood pressure at home regularly. My readings are all over the place and different from the reading at my most recent doctor visit. Why is my blood pressure so erratic?
A. There can be many reasons for erratic blood pressure readings. For one thing, blood pressure naturally fluctuates over the course of a day. It is generally lowest when you're sleeping and peaks during the day. If you check your blood pressure at different times, you may be seeing that natural variation. Blood pressure is also affected by physical activity, eating, caffeine, and stress.