If you have ever been to the doctor, you’ve probably had a blood pressure test. The familiar test using a cuff and blood pressure monitor is quick, easy, noninvasive, and painless.

Blood Pressure Test

Adults should have their blood pressure checked by a health-care professional at least once every two years. Those with high blood pressure, heart disease, or cardiovascular risk factors are typically advised to get more frequent blood pressure tests. Children age 3 and up usually have a blood pressure test as part of their annual checkup.

Before the test

No special preparation is needed for a routine blood pressure test. However, if the main reason for your doctor’s appointment is to check your blood pressure, you might be asked to take steps to ensure that you get the most accurate reading possible. These steps include not smoking or drinking coffee for 30 minutes before the test, using the bathroom prior to testing, and sitting down for five minutes right before the test is done.

During the test

During the test, an inflatable cuff is placed around your upper arm. This cuff is attached to a monitor, called a sphygmomanometer, which has a dial or digital display. First the cuff is inflated until it gets tight, which compresses a large artery in your arm and momentarily stops blood flow there. Then air is slowly let out of the cuff.

In the classic test, as the cuff deflates, a health-care professional listens to the artery with a stethoscope and watches the dial or display. When the first sound is heard as blood starts pulsing through the artery again, the number showing on the dial or display is the systolic pressure (first blood pressure number). When the last sound is heard, the number showing is the diastolic pressure (second blood pressure number).

Blood pressure can also be measured automatically using an electronic device that senses the pulses and records the numbers, but the principle is the same. Whether blood pressure is measured manually or automatically, it takes only about a minute to do the test.

After the test

Everyone, healthy or not, should know their blood pressure numbers. If your doctor doesn’t volunteer the numbers, be sure to ask. If high blood pressure is suspected, you may need to come back and repeat the test on multiple occasions. Blood pressure naturally varies throughout the day and from one day to the next, so this gives the doctor a more complete picture of your overall blood pressure status.

Home Blood Pressure Monitoring

In addition to getting periodic blood pressure tests at the doctor’s office, many people benefit from tracking their blood pressure at home. The American Heart Association recommends home blood pressure monitoring for everyone with high blood pressure. The additional data it provides can help the doctor evaluate how well treatment is working over time.

Home monitoring can also be helpful for people who have trouble getting an accurate blood pressure reading at the doctor’s office.

White-coat hypertension occurs when blood pressure is consistently higher than usual at the doctor’s office due to anxiety and stress. If home monitoring shows that blood pressure is actually normal most of the time, unnecessary treatment can be avoided.

Masked hypertension occurs when blood pressure is consistently lower than usual at the doctor’s office. This might be due to greater stress at home or to tobacco, alcohol, or caffeine use there. If home monitoring shows that blood pressure is actually high much of the time, appropriate treatment can be started.