Blood pressure is a measurement of the force applied to the walls of your arteries as your heart pumps blood through your body.
Your blood pressure can be measured at home, or at your health care provider's office, a fire station, pharmacies, and many other places.
Diastolic blood pressure; Systolic blood pressure; Blood pressure reading; Measuring blood pressure
Your arm should be supported, with your upper arm at heart level, back supported, legs uncrossed, and feet on the floor. Your upper arm should be bare, with your sleeve comfortably rolled up.
You or your health care provider will wrap the blood pressure cuff snugly around your upper arm. The lower edge of the cuff should be 1 inch above the bend of your elbow.
Inflating the cuff too slowly or not high enough may cause a false reading. If you loosen the valve too much, you won't be able to determine your blood pressure.
The procedure may be done two or more times.
Measuring your blood pressure is best done after you rest for at least 5 minutes.
Do not take your blood pressure when you're under stress, have consumed caffeine or used a tobacco product in the past 30 minutes, or have recently exercised.
Take two or three readings at a sitting, 1 minute apart, while resting in a seated position. When measuring your blood pressure outside of a medical office, it is important to note the time of the readings.
Your doctor may suggest that you do your readings at certain times. A common recommendation is to take your blood pressure in the morning and at night for a week. That way, you will get at least 12 readings to help your doctor make decisions about your blood pressure treatment.
You will feel slight discomfort when the blood pressure cuff is inflated to its highest level.
Because there are no symptoms, you can have high blood pressure and not know it. High blood pressure may be found when you visit your health care provider for other reasons.
Diagnosing high blood pressure early can help prevent heart disease, stroke, eye problems, or chronic kidney disease.
All adults should have their blood pressure checked every 2 years, if their blood pressure was less than 120/80 mmHg at the most recent reading. You should have it checked yearly if your last reading was 120-139/80-89 mm Hg.
If you have high blood pressure, diabetes, heart disease, kidney problems, or certain other conditions, you should have your blood pressure checked more often -- at least every year.
Blood pressure readings are usually given as two numbers -- for example, 120 over 80 (written as 120/80 mmHg). One or both of these numbers can be too high.
Normal blood pressure is when the top number (systolic blood pressure) is below 120 most of the time, and the bottom number (diastolic blood pressure) is below 80 most of the time (written as 120/80 mmHg).
If your blood pressure numbers are 120/80 or greater but below 140/90, it is called pre-hypertension. If you have pre-hypertension, you are more likely to develop high blood pressure.
High blood pressure (hypertension) is when the top number (systolic blood pressure) is 140 or more most of the time or the bottom number (diastolic blood pressure) is 90 or more most of the time. (written as 140/90 mmHg).
If you have diabetes, heart disease, or kidney problems, or if you had a stroke, your doctor may want your blood pressure to be lower.
Most of the time, high blood pressure does not cause symptoms. For most patients, high blood pressure is found when they visit their health care provider or have it checked elsewhere.
See also: Preeclampsia to learn about high blood pressure in pregnant women.
It is normal for your blood pressure to be different depending on the time of day:
Blood pressure readings taken at home may be a better measure of your current blood pressure than those taken at your doctor's office, as long as you make sure your machine is accurate. You can ask your health care provider to compare your home readings with those taken in the office.
Many people become nervous at the doctor's office and have higher readings than they normally would at home. This is called white coat hypertension.
Victor RG. Systemic hypertension: Mechanisms and diagnosis. In: Bonow RO, Mann DL, Zipes DP, Libby P, eds. Braunwald's Heart Disease: A Textbook of Cardiovascular Medicine. 9th ed. Philadelphia, Pa: Saunders Elsevier; 2011:chap 45.
Victor RG. Arterial hypertension. In: Goldman L, Schafer AI, eds. Cecil Medicine. 24th ed. Philadelphia, PA: Saunders Elsevier; 2011:chap 67.