All I have to do is sit in my doctor’s office and I know my blood pressure will be high,” a friend of mine says. “I’m a nervous wreck waiting for more bad news!” And it’s true—blood pressure can go up just because you are in your health care provider’s office. This condition is so common, it has a name—“white coat” high blood pressure. This is named after the white coats that some health care providers wear.

So how can you get an accurate idea of what your blood pressure is normally if it skyrockets every time you go to your healthcare provider’s office? One way is to buy a home blood pressure monitor at your local Costco pharmacy.

What do the numbers mean?

Your blood pressure numbers measure the pressure in your blood vessels when your heart beats and when it is at rest. Blood pressure is described by two numbers – for example, 120/80. This is the blood pressure target recommended by the American Heart Association for most people. The first number (120) is the pressure in your heart and blood vessels when your heart is pumping; this is called “systolic blood pressure.” The second number (80) is the pressure when your heart is at rest; this is called “diastolic blood pressure.” The blood pressure goal for people with diabetes is 130 over 80 or lower. You will often see this written as 130/80.

Your blood pressure is constantly changing. It will be different when you are moving around as opposed to sitting. Your blood pressure also changes depending on your mood—whether you are calm or upset. If your numbers are usually higher, your health care provider may prescribe blood pressure medicine, or change the type or amount of blood pressure medicines you are already taking.

At-home blood pressure readings

The blood pressure reading you get at your health care provider’s office is helpful, but it is only one reading, taken once in a while. If you check your blood pressure in the comfort of your own home, you may get a more realistic look at the everyday ups and downs of your blood pressure. Keep a log of your blood pressure readings so you can show them to your health care provider at your next office visit. Besides avoiding white coat high blood pressure, the numbers you get when you check at home also tell you and your health care provider if your blood pressure medicines are working. Remember, your blood pressure may be high even if you feel fine. Check your blood pressure around the same time each day. You may choose to check your blood pressure in the morning after breakfast or in the evening before dinner. Try to check your blood pressure on days that you work or are active, and on days that you don’t work or are less active. Also, try to check your blood pressure on the same arm each time you do it. This way you can learn if the stress of work or activity raises your blood pressure.

What type of blood pressure monitor should I buy?

You will find arm and wrist models for home blood pressure monitoring. Most devices for home use include a band (or cuff) that goes around your arm and has a digital display for the readings. If you buy a manual blood pressure monitor, which you pump up by hand, you will need to squeeze a bulb to pump air into the cuff and press a button to release the air. Your blood pressure then appears on a large, easy-to-read screen. If you buy an automatic blood pressure monitor, which automatically pumps up, you just wrap the cuff around your arm, press a button and your blood pressure appears on the screen. If you buy a wrist blood pressure monitor, you wrap the cuff around your waist, press a button and your blood pressure will appear on the screen.

How can I get the most accurate readings?

First, it is important to make sure that the cuff is large enough for your arm. If the cuff is too large or too small, the results will not be accurate. The manufacturer prints guidelines for choosing a blood pressure cuff on the box so you can determine what size you need. (Note: Using the right size cuff is also important when your blood pressure is taken by your healthcare provider. Don’t be shy about asking the person taking your blood pressure to find a larger or smaller cuff, if that’s what you need.)

When you or anyone else measures your blood pressure, you should be seated with your arm supported on a table. If there is no table available, support your arm with your opposite hand. Blood pressure should be measured on your right arm if you are right-handed and your left arm if you are left-handed. Also, it is important to limit body movements, including talking, while taking your blood pressure.

Using the blood pressure monitor incorrectly is the most common cause of false readings. Take your blood pressure monitor to your healthcare provider’s office to have someone check that you are using it properly. You can then compare the reading you get on your monitor with the one they get on their monitor to make sure yours is working properly.

Do health plans pay for blood pressure monitors?

Most health plans do not pay for a home blood pressure monitor. But, once you buy the blood pressure monitor, you do not have to buy any other supplies. The cost of a blood pressure monitor depends on the features it offers, such as extra-large displays and pulse readings. Look for coupons and remember that a blood pressure monitor can be deducted from your taxes as a medical expense.