If your blood pressure is normal (less than 120/80), get it checked at least every 2 years.
If your blood pressure is borderline high (called prehypertension) — systolic blood pressure between 120 and 139 or diastolic blood pressure of 80 to 89 — check it at least every year.
If your reading is 140/90 or higher, you have high blood pressure and need to see your doctor. You may need to start medication.
How often should you check? At first, take your blood pressure twice a day for a week. The best times are early in the morning and again in the evening. After you’ve done this for a week, once or twice a month or whatever your doctor recommends is fine.
“It can be a very effective way to see if blood pressure medications are doing the trick. It can also be useful to monitor for the side effect of blood pressure that is too low.
The latest evidence for the benefits of home blood pressure monitoring comes from researchers in Minnesota. They studied 450 people with hypertension, more commonly known as high blood pressure. All had blood pressures higher than deemed healthy—above 140/90, or above 130/80mmHg if they had diabetes or kidney disease.
Half of these adults don’t have it under control. High blood pressure increases the risk for heart disease and stroke, the leading causes of death in the United States. About half of the volunteers were given home blood pressure monitors capable of electronically sending readings to a secure website. After being shown how to use their monitors, the volunteers were asked to send six readings each week. That information was assessed by pharmacists, who could adjust medications if needed and offer advice on lifestyle changes that could improve blood pressure. The other volunteers received usual care from their primary care providers.
At every step of the way, people in the home monitoring group had more success getting their blood pressure under control than people who had received only usual care. At the end of the trial, 72% of those doing home monitoring had their blood pressure under control, compared to 57% of the usual care group. The benefits persisted six months after the program had ended.