Blood pressure test

Date Updated: 05/27/2022

Overview

A blood pressure test measures the pressure in the arteries as the heart pumps. A blood pressure test may be done as a part of a routine health checkup or as a screening for high blood pressure (hypertension). Some people use home monitors to check their blood pressure at home.

Why it's done

A blood pressure test is a routine part of most health care checkups. Blood pressure screening is an important part of general health care.

How often you should get your blood pressure checked depends on your age and overall health.

People age 18 and older with optimal blood pressure and no heart disease risk factors should have a blood pressure test at least once every 2 to 5 years.
People age 40 and older — or younger with an increased risk of high blood pressure — should have a blood pressure test every year. Risk factors for high blood pressure include obesity and being Black.
People who have chronic health conditions, such as high or low blood pressure or heart disease, may need to have blood pressure tests more often.

Your health care provider may also suggest that you check your blood pressure at home. Automated home blood pressure monitors are easy to use. Some can be connected to a computer or cellphone, allowing you to send the information to an online medical record. Ask your provider if this is an option for you.

It's a good idea to keep a log of your home blood pressure readings. Also have your care provider check your monitor once a year to make sure you are getting accurate readings.

Home blood pressure monitoring isn't a substitute for visits to your health care provider.

Risks

A blood pressure test is simple, quick and usually painless. However, the blood pressure cuff squeezes the arm while it inflates. Some people find this slightly uncomfortable. The feeling lasts for only a few seconds.

How you prepare

No special preparations are usually needed for a blood pressure test. But the following steps may provide the most accurate measurement:

Do not smoke, exercise or use caffeine for 30 minutes to an hour before the test. Such activities increase blood pressure and heart rate.
Wear a short-sleeved shirt so that the blood pressure cuff can be placed more easily around your arm.
Relax in a chair for at least five minutes before the test.
Tell your health care provider about the medications you take. Some drugs may affect blood pressure.

What you can expect

During the procedure

A blood pressure reading is usually taken while a person is seated in a chair with the feet flat on the floor. The arm should rest comfortably at heart level.

The blood pressure cuff goes around the top part of the arm. The bottom of the cuff is just above the elbow. It's important that the cuff fits. Blood pressure readings can vary if the cuff is too big or too small.

Blood pressure readings can be taken with the help of a machine. This is called an automated measurement. When a machine isn't used, this is called a manual measurement.

For a manual blood pressure measurement, the care provider places a stethoscope over the major artery in the upper arm (brachial artery) to listen to blood flow.
The cuff is inflated with a small hand pump.
As the cuff inflates, it squeezes the arm. Blood flow through the artery stops for a moment.
The health care provider opens a valve on the hand pump to slowly release the air in the cuff and restore blood flow. The provider continues to listen to blood flow and pulse and records the blood pressure.

For an automated measurement, the blood pressure cuff automatically inflates and measures the pulse. In this case, a stethoscope is not needed.

It takes about one minute to get a blood pressure measurement.

After the procedure

If your blood pressure is high or low, you'll likely need to have at least three more blood pressure tests, spaced at least a week apart, to determine if you need treatment. Blood pressure can vary from moment to moment and day to day.

Results

Your health care provider can tell you your blood pressure results right away after the test.

Blood pressure is measured in millimeters of mercury (mm Hg). A blood pressure measurement has two numbers:

The top number (systolic) is the pressure of the blood flow when the heart muscle squeezes (contracts), pumping blood.
The bottom number (diastolic) is the pressure measured between heartbeats.

The American College of Cardiology and the American Heart Association divide blood pressure into four general categories. Ideal blood pressure is categorized as normal. Here's a look at blood pressure categories and what they mean. If the top and bottom numbers fall into two different ranges, the correct blood pressure category is the higher one.

Top number (systolic) in mm Hg	And/or	Bottom number (diastolic) in mm Hg	Blood pressure category*	What to do
Below 120	and	Below 80	Normal blood pressure	Maintain or adopt a healthy lifestyle.
120-129	and	Below 80	Elevated blood pressure	Maintain or adopt a healthy lifestyle.
130-139	or	80-89	Stage 1 high blood pressure (hypertension)	Maintain or adopt a healthy lifestyle. Talk to your provider about taking one or more medications.
140 or higher	or	90 or higher	Stage 2 high blood pressure (hypertension)	Maintain or adopt a healthy lifestyle. Talk to your provider about taking more than one medication.
Sources: American College of Cardiology; American Heart Association

*Ranges may be lower for children and teenagers. Talk to your child's provider if you think your child might have high blood pressure.

If you have high blood pressure, making a few lifestyle changes can improve your heart health.

Reduce salt (sodium). The American Heart Association recommends that healthy adults have no more than 2,300 milligrams (mg) of sodium a day. Ideally, most adults should limit salt to less than 1,500 mg a day. Check the amount of salt in processed foods, such as canned soups and frozen foods.
Eat healthy foods. Choose fruits, vegetables, whole grains and low-fat dairy foods. Eat less saturated fat and total fat.
Avoid or limit alcohol. Alcohol can raise blood pressure. If you choose to drink alcohol, do so in moderation. For healthy adults, that means up to one drink a day for women and up to two drinks a day for men.
Don't smoke. If you need help quitting, ask your provider about strategies that can help. Also try to avoid secondhand smoke.
Manage weight. Having too much body weight is a risk factor for high blood pressure. Losing even just a few pounds can lower blood pressure.
Exercise regularly. Staying active helps lower your blood pressure and manage your weight. The Department of Health and Human Services recommends that most healthy adults get at least 150 minutes of moderate aerobic activity or 75 minutes of vigorous aerobic activity a week, or a combination of the two.

If lifestyle changes do not successfully manage your blood pressure, your health care provider may recommend medication. Together, you and your provider can discuss the best treatment options for you.