Prehypertension doesn't cause symptoms. In fact, severe high blood pressure may not cause symptoms.
The only way to detect prehypertension is to keep track of your blood pressure readings. Have your blood pressure checked at each doctor's visit — or check it yourself at home with a home blood pressure monitoring device.
When to see a doctor
Ask your doctor for a blood pressure reading at least once every two years. You may need more-frequent readings if you have prehypertension or other risk factors for cardiovascular disease.