Know your blood pressure

​​Know your blood pressure numbers​

Knowing your blood pressure can help you stay healthy and reduce your risk of serious health conditions. Many people know their age, height and weight. Fewer people know their blood pressure numbers.

Blood pressure is the force of blood moving through your blood vessels. If it stays too high, it can put extra strain on your heart, blood vessels and other organs.

High blood pressure often has no symptoms. You can feel well and still have high blood pressure. The only way to know your blood pressure is to have it measured.

The Know Your Numbers Initiative encourages adults in Jersey to:

• measure their blood pressure
• record their readings
• understand what their readings mean
• take action if their readings stay outside the recommended range

Knowing your numbers can help you get support early and reduce your risk of stroke, heart attack and kidney disease.

List of participating pharmacies

The pharmacies participating in the Know Your Numbers Initiative from Monday 7 September to Sunday 13 September 2026 are:

Get your blood pressure measured

Your GP may check your blood pressure during an appointment, health check or medication review.

Many pharmacies in Jersey also offer blood pressure checks. 

Pharmacy teams can:

• measure your blood pressure
• show you how to use a home monitor
• give healthy lifestyle advice
• direct you to other services if needed

Contact your community pharmacy before visiting to check if they offer this service.

How to measure your blood pressure at home

You can buy a home blood pressure monitor from most community pharmacies.

Choose a clinically validated monitor. This helps make sure your readings are accurate. Your pharmacist can help you choose a suitable monitor and the right cuff size for your arm.

The cuff must fit properly. A cuff that is too small or too large can affect the reading.

Follow the instructions provided with your monitor.

When taking a reading:

• sit comfortably with your back supported
• keep both feet flat on the floor
• support your arm on a table or firm surface, so the upper arm is at heart level
• stay still and relaxed

For the most reliable reading:

• do not measure your blood pressure within 30 minutes of exercise
• avoid caffeine, smoking and large meals for at least 30 minutes before measuring
  
• place the cuff directly on your upper arm
• loosen or remove tight clothing from your arm
• sit somewhere quiet

Exercise, smoking, caffeine and eating can temporarily increase blood pressure.

If a reading is higher or lower than expected, sit quietly for a few minutes and take a second reading. Record both readings.

If a healthcare professional has asked you to monitor your blood pressure at home, follow their advice about how often to take readings.

Make sure that you record:

• the date and time
• your systolic reading (top number)
• your diastolic reading (bottom number)
• anything that may have affected the reading, such as exercise, stress, poor sleep or illness

Understand your blood pressure reading

A blood pressure reading contains 2 numbers and is measured in millimetres of mercury (mmHg).

For example: 120/80mmHg

The first number is your systolic blood pressure. It measures the pressure in your arteries when your heart pumps blood around your body.

The second number is your diastolic blood pressure. It measures the pressure in your arteries when your heart rests between beats.

What is a healthy blood pressure

Blood pressure readings should be considered alongside:

• your age
• your medical history
• any medicines you take
• whether you are pregnant
• when the reading was taken

A healthy range is between 90/60mmHg and 140/90mmHg.

Healthcare professionals may use different thresholds when deciding if you need monitoring, assessment or treatment.

A single reading outside the usual range does not always mean there is a problem. Blood pressure changes throughout the day and can be affected by illness, stress, exercise and other factors.

Get urgent medical help

Get urgent medical help if you have:

• chest pain or pressure
• severe shortness of breath
• sudden weakness or numbness, particularly on one side of the body
• sudden difficulty speaking
• sudden confusion
• a sudden, severe headache
• fainting or loss of consciousness
• sudden changes to your vision, such as blurred, double or lost vision 

Do not wait to take a blood pressure reading if you have serious symptoms.

In an emergency:

• call 999 for an ambulance
• go to the Emergency Department

Causes of high blood pressure

Several factors can increase your risk of developing high blood pressure.

You cannot change some risk factors, including:

• age
• family history
• some medical conditions

Lifestyle factors can also increase your risk, including:

• eating too much salt
• being overweight
• not being physically active
• smoking
• drinking too much alcohol
• having a high caffeine intake
• poor sleep
• long-term stress

Lower your risk of high blood pressure

High blood pressure can often be improved through lifestyle changes and, if needed, treated with medication.

If your blood pressure is high, get advice from a healthcare professional.

Further information

You can find more information about blood pressure, monitoring and treatment at Blood Pressure UK.

For information about clinically validated home blood pressure monitors, go to British and Irish Hypertension Society (BIHS)​.