Hero - woman checking her BP

Getting a blood pressure check


A blood pressure check is simple, quick and painless, and it could save your life. It’s easy to arrange as well.

Here you can find out what a blood pressure test involves and where you can have a free check.


Getting a check

Before your check, take a minute to sit comfortably and take a deep breath. If you’ve had to rush to get there your heart will be working hard and your blood pressure will go up. If you can, arrive five or ten minutes early so you can take a moment to relax.


Measuring your blood pressure  

Your GP, nurse, or other professional measuring your blood pressure, will ask you to sit comfortably and rest one arm on the table. They will then place a fabric cuff around your upper arm – wear a T-shirt or loose clothes so that you can roll up your sleeves easily.

The inflatable cuff is attached to a small machine via a plastic tube. Your GP will inflate the cuff using a small hand-held pump, and as the cuff deflates the machine will read your blood pressure and display the numbers on a screen. This only takes a minute or two.

Woman blood pressure check white coat doctor


Sometimes your doctor might use a hand-held gauge, which looks a lot like a clock face, and a stethoscope to measure your blood pressure, rather than a machine. This is called an aneroid sphygmomanometer – a sphygmomanometer is a device used to measure your blood pressure.

Your GP might check your pulse before measuring your blood pressure, because an irregular pulse can mean the automatic monitors don’t give an accurate reading. In which case, they will use a stethoscope instead. 


Different types of blood pressure monitor

You might come across some different types of blood pressure monitor. For example, some GP surgeries and hospitals have a large machine that allows you to measure your blood pressure yourself. You sit or stand in front of the machine and place your arm or hand inside. You wait for a minute or two while it measures your blood pressure, then your number will be displayed on a screen, and it might give you a print out with your numbers on.   

There are also monitors you can buy to use at home.

Older woman BP check woman doctor


What does a blood pressure reading look like?

Your blood pressure reading will consist of two numbers – a high one and a low one, e.g. 120 and 80. It will be written like this: 120/80mmHg.

The higher number is when your heart pumps and forces blood through your arteries. This is your systolic blood pressure, it’s when the pressure against your artery walls is highest. The lower number is when your heart is relaxed and your blood pressure is at its lowest. This is your diastolic blood pressure. 

Read more about what the numbers mean.


What happens next?

Your doctor will ask you some questions to find out more about your overall health and if you might be at risk of health problems in the future, for example, if others in your family have had high blood pressure. What happens next will depend on your blood pressure reading.

If your reading is in the healthy range
If your reading is below 120/80mmHg (mmHg is the unit of measurement, it means millimetres of mercury), and you are in generally good health, there is probably no need to have further tests. This is the ideal blood pressure reading. 

All adults should have another test within five years, as blood pressure can creep up over time. 

Have a look to see if there are any healthy changes you could make to your lifestyle to keep your blood pressure healthy for life. 

If your reading is a little raised
If your numbers were between 120/80mmHg and 139/89mmHg your doctor might want to talk to you about lifestyle changes you can make to look after your blood pressure and your health. 

They may also want to keep an eye on your blood pressure and your doctor will discuss with you when you should have another check-up.

If your reading is high
If your reading is over 140/90mmHg your doctor will try to find out more about your blood pressure and your overall health. 

They will probably take more measurements in the same appointment to see if the next ones are any lower. They may also measure your blood pressure in both arms. If one arm has a reading much higher than the other, they will repeat the measurements. And in future will use the arm with the higher reading.

A one-off high reading doesn’t necessarily mean you have high blood pressures, as your blood pressure varies throughout the day. It could also be raised by the stress of being in clinic, this is known as white coat syndrome. 

Your doctor might want to test your blood pressure again soon or ask you to measure it yourself at home to find out more, either with a home monitor or with 24-hour monitoring, they might also suggest some other simple tests

Your doctor will talk to you about making healthy changes to your lifestyle. If your blood pressure is very high, they might talk to you about medications to lower it during the same appointment, and you might be referred to a specialist.

If your blood pressure check was not with your GP and your reading was high, make an appointment to see your GP so they can find out more.


What is white coat syndrome? 

White coat syndrome is when your blood pressure is raised due to the stress of being in clinic, so your reading is higher than it would be if you measured it at home. It’s also known as the white coat effect and is fairly common. The term ‘white coat’ refers to the white coats traditionally worn by doctors.

Most people are more tense than usual in medical settings and might not even realise it. So your blood pressure can be raised even if you don’t feel stressed.

On average, the top (systolic) number tends to be about 10mmHg higher in a clinic than at home. The bottom numbers tends to be about 5mmHg. Some people’s blood pressure will be affected more than others, and if you feel very worried or stressed it could be raised by as much as 30mmHg. 

Getting an accurate reading

When you have your blood pressure checked in clinic, arrive a few minutes early if you can and take a few minutes to sit quietly and relax first.

Health professionals are aware of white coat syndrome, so if you have a high reading in clinic, they might want you to measure your blood pressure yourself away from the clinic. You can do this using a home blood pressure monitor, or with 24-hour monitoring, where you wear a small monitor attached to a belt for a day as you go about your usual routine.

These can give a better idea of what your blood pressure is really like as you’ll be in familiar surroundings, away from the stress of the clinic. 


White coat hypertension

White coat hypertension is where your blood pressure readings are over 140/90mmHg in clinic – the cut-off for diagnosing high blood pressure – but are lower than 140/90mmHg at home. 

This is a slightly different term to white coat syndrome or white coat effect, which refers to your blood pressure being higher in clinic regardless of what your numbers are, whether they’re high or low.

If you have white coat hypertension, your blood pressure could creep up into high blood pressure. Your GP will suggest how often you should have a check to keep an eye on it. You could also measure your blood pressure at home using a home monitor. Eating healthily and being active will help you take care of your blood pressure.




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