Understanding blood pressure

Blood pressure is the 'force' that keeps blood moving through your arteries once it has been pumped from your heart. Blood pressure readings can give an indication of how hard your heart is working and are an important part of a general health assessment.  Managing medicines and monitoring blood pressure levels are important for people living with high blood pressure.


What is blood pressure?

How is blood pressure measured?

Blood pressure is measured using a sphygmomanometer. A specialised inflatable cuff wraps around your upper arm and connects to a device for measuring and recording blood pressure.  An electronic device reads the pressure directly from the cuff. 

Blood pressure measurements are generally more accurate if taken when you are sitting down and relaxed.

How is blood pressure recorded?

Blood pressure is is recorded as two numbers, one over the other (eg, 120/80 mmHg, read as '120 over 80').The first number shows the pressure when the heart pumps blood into the arteries (the 'systolic blood pressure' or SBP), and the second number is the pressure in the arteries when the heart relaxes (the 'diastolic blood pressure' or DBP).

The higher the numbers, the harder your heart is working to move blood through your arteries.

What is high blood pressure?

In most cases a person is considered to have high blood pressure if their readings are consistently above 140/90 mmHg. There is no firm rule that defines when blood pressure is too high for a particular person, but for most people the lower the better.

Your health professional will determine your ideal blood pressure goal based on your individual circumstances (including age, medical and family history and medicines).

National Heart Foundation guide to blood pressure ranges

  • Normal: generally less than 120/80 mmHg (ie, systolic blood pressure less than 120 and diastolic blood pressure less than 80 mmHg).
  • Normal to high: between 120/80 and 140/90 mmHg.
  • High: 140/90 mmHg or higher.
  • Very high: 180/110 mmHg or higher.

Your health professional will most likely measure your blood pressure several times on different occasions to confirm whether or not you have high blood pressure.

Is low blood pressure a problem?

Low blood pressure (also called hypotension) is usually only a problem if it causes symptoms or results in adverse effects. A relatively low blood pressure may be of no concern in fit, healthy people.

If you experience symptoms such as light-headedness, dizziness and fainting, you should talk to your health professional.

What causes high blood pressure?

Risk factors for high blood pressure

There are certain risk factors for developing high blood pressure that you can't control. These include your age, ethnic background, or family history of high blood pressure or other cardiovascular disease.

There are some risk factors for developing high blood pressure that you can change. These include drinking less alcohol, being more physically active, and eating a balanced diet.

Quitting smoking is essential to improve your overall heart health.

Lifestyle, along with genetic and environmental factors, can contribute to your risk of developing high blood pressure.

Find out more about lifestyle choices for better health.

Managing high blood pressure

Managing your medicines and monitoring and recording your blood pressure are important for people living with high blood pressure.

Manage your medicines

Many people who have high blood pressure do not experience any symptoms. This sometimes makes it difficult to see the benefit of taking a medicine every day. Although you may not feel any different, the medicines should be reducing your blood pressure and, therefore, your risk of stroke, heart and kidney disease.

Do not stop taking your medicine, even if you feel better. If you have side effects, talk to your doctor first before stopping any medicines you have been prescribed. There are many different types of medicine you and your doctor can try that will control your blood pressure and minimise the risk of side effects.

Discuss your medicines and lifestyle with your health professional so they can help you achieve your blood pressure goals.

Make positive lifestyle changes

Positive lifestyle changes can significantly lower your blood pressure and reduce your risk of developing cardiovascular disease. For example, if you stop smoking, within two years you can reduce your risk of having a heart attack or stroke. Other lifestyle changes such as eating a healthier diet, drinking less alcohol, exercising more and losing weight if you are overweight will help reduce your blood pressure.

Managing your blood pressure lowering medicines

Tips for managing your medicines

  • Take your medicine(s) every day.
  • Don't stop taking your medicine(s).
  • Speak to your doctor before you stop taking a medicine.
  • Keep a list of all your medicines.

Some people are concerned about taking a medicine every day, even when they feel better. Alternative medicines may be available if you are experiencing side effects. Your doctor will be able to discuss these concerns with you.

Keep a list of all your medicines

It can sometimes be difficult to keep track of all your medicines. A medicines list is a useful way to keep all the information about your medicines together. It may also be helpful if you need to see more than one doctor. You can use a medicines list to record:

  • all your medicines, including prescription, non-prescription and complementary medicines
  • what each medicine is for
  • how much of each medicine to take
  • when and how to take each medicine.

Taking your blood pressure medicines is important

Taking your blood pressure lowering medicines as prescribed by your doctor has an important effect on your health outcomes.

Patients with high blood pressure who take their medicine less than 20% of the time are twice as likely to be hospitalised as those who take their blood pressure lowering medicines as prescribed.

Stick to your medicine regimen

Many people find their medicine regimen difficult to stick to. Reasons why people have difficulty taking all of their medicines at the right time and dose include:

  • having to remember to take several medicines at once
  • having a complicated medicine schedule
  • having a chronic condition which means they need to take medicine for a long time
  • sometimes forgetting to take their medicines
  • their previous medicines may not have worked for them
  • they experienced unpleasant side effects or feelings
  • their treatment may be constantly changing
  • they didn't see immediate benefits from the medicines they were taking
  • they 'felt better' and therefore decided they didn't need the medicine
  • they may not have easy access to a doctor or pharmacist.

If you have questions or concerns about your medicines, speak to your doctor. Asking questions will help you get the information you need to make better decisions about your medicines.