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High blood pressure

How does my doctor diagnose high blood pressure?

Because you don't get any symptoms with high blood pressure, you probably won't go to your doctor to ask for it to be checked. You're more likely to have your blood pressure measured when you go to see your doctor for something else.

For example, if you're going to your doctor to discuss treatment for menopause or because you've been feeling depressed, your doctor may suggest a blood pressure check.

Having your blood pressure checked

The only way to know whether you have high blood pressure is to have it measured. You're probably familiar with the simple blood pressure test. To find out more, see The blood pressure test.

Your blood pressure can go up and down, so your doctor may need to measure it several times before deciding whether it's high. Everyday things such as being worried about seeing your doctor or having rushed to your appointment can affect your systolic pressure (top number) by more than 10 points on the blood pressure scale. To learn more, see What the numbers tell you.
Even during one visit your doctor may measure your blood pressure twice to make sure the reading is correct.

Source:
Chobanian AV, Bakris GL, Black HR, et al.
Seventh report of the Joint National Committee on prevention, detection, evaluation, and treatment of high blood pressure.
Hypertension. 2003; 42: 1206-1252.

¹
Unless your blood pressure is very high, your doctor will probably measure your blood pressure two more times before deciding whether you need treatment.

Source:
Chobanian AV, Bakris GL, Black HR, et al.
Seventh report of the Joint National Committee on prevention, detection, evaluation, and treatment of high blood pressure.
Hypertension. 2003; 42: 1206-1252.

¹

Other tests

If you have high blood pressure, your doctor may do some other tests to try to find out what's causing it. Your doctor will also want to check whether your high blood pressure has affected your body.

You may have:

Source:
Chobanian AV, Bakris GL, Black HR, et al.
Seventh report of the Joint National Committee on prevention, detection, evaluation, and treatment of high blood pressure.
Hypertension. 2003; 42: 1206-1252.

A blood test (to look for

diabetes
Diabetes is a condition that causes too much sugar to circulate in your blood. It happens when your body stops making a hormone called insulin (type 1 diabetes) or when insulin stops working (type 2 diabetes).

diabetes, check your

cholesterol
Cholesterol is made by your liver or absorbed from food. It is used by your body to make bile acids (which help your intestines absorb nutrients) and steroid hormones (like testosterone or estrogen). Cholesterol is also an important part of cell membranes, which are the structures that surround cells. "Good cholesterol" is called HDL; "bad cholesterol" is LDL.

cholesterol, and check how well your

kidney
Your kidneys are organs that filter your blood to make urine. You have two of them, on either side of your abdominal cavity, toward your back.

kidneys are working)
A urine test (to see how well your kidneys are working)
An

electrocardiogram
An electrocardiogram is a test that measures the electrical activity in your heart. The test doesn't hurt. It tells doctors how well your heart is working. It is called EKG for short.

electrocardiogram (or ECG, a test to see if your heart is working properly).

Your doctor may also ask you:

About your health
Whether you smoke
How much alcohol you drink
Whether anyone else in your family has high blood pressure or

heart disease
You get heart disease when your heart isn't able to pump blood as well as it should. This can happen for a variety of reasons.

heart disease.

These tests and questions help your doctor find out if you have any other risk factors for

heart disease
You get heart disease when your heart isn't able to pump blood as well as it should. This can happen for a variety of reasons.

heart disease besides high blood pressure, such as high cholesterol. (Having a risk factor for a disease increases your chance of getting a certain condition, but doesn't guarantee that you will.) The results of the tests will also help your doctor decide whether you need treatment.

To find out more, see Risk factors explained.

Your doctor may also do some special tests to see if you have a disease that has caused the high blood pressure. If your blood pressure is dangerously high, you may need to go to the hospital right away for treatment.

Checking your blood pressure at home

If your blood pressure reading is very different every time your doctor measures it, they may suggest that you measure your own blood pressure at home.

Also, some people's blood pressure goes up when they go to see their doctor but is normal when they're at home. This is called white-coat hypertension, after the white coats that doctors sometimes wear. It's thought that these people feel stressed when they go to see their doctor and this raises their blood pressure. If your doctor thinks you might have this problem, they also may advise you to measure your blood pressure at home.

Your doctor might also want to have your blood pressure measured continually over 24 hours.

¹ This is called ambulatory blood pressure monitoring, or ABPM for short. If you have this type of monitoring, you wear a device that measures your blood pressure as you go about your everyday life.

Sources for the information on this page:

Chobanian AV, Bakris GL, Black HR, et al.Seventh report of the Joint National Committee on prevention, detection, evaluation, and treatment of high blood pressure.Hypertension. 2003; 42: 1206-1252.

This information was last updated on Jul 02, 2009

This information is for educational use only, and is not a substitute for prompt professional medical advice. Readers should always consult a physician or other professional for advice and treatment.
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