Patient information from BMJ

Understanding your blood pressure reading

Last published:Dec 06, 2021

When your doctor tells you what your blood pressure is, he or she will give you two numbers. For example, your doctor may say that your blood pressure is '120 over 80'. This would be written as 120/80.

• The first, higher number is called the systolic pressure. It measures the pressure of the blood when your heart pumps blood out.

• The second, lower number is called the diastolic pressure. This is the pressure measured when your heart relaxes and fills up with blood.

People usually find out they have high blood pressure after a routine blood pressure check. If you have a high reading, you’ll need to have your blood pressure measured on two or more occasions to confirm that you have high blood pressure. You should also have your blood pressure measured in both arms.

If your numbers are higher than they should be, your doctor will probably give you lifestyle advice on ways to lower your blood pressure (for example, through diet, exercise, and stopping smoking). Most people are also prescribed medicines to lower their blood pressure.

Here is a general guide as to what your doctor might recommend depending on how high your blood pressure is. However, treatment can vary from person to person. For example, treatment recommendations may be different for someone who is older or has other health problems, such as kidney disease or diabetes.

Blood pressure from 130 to 139 (systolic) or 85 to 89 (diastolic)

This is sometimes called 'high-normal' blood pressure. It means you may have an increased chance of developing high blood pressure. Your doctor may give you advice on how to reduce your blood pressure by changing what you eat or do (lifestyle advice).

Blood pressure from 140 to 159 (systolic) or 90 to 99 (diastolic)

This is sometimes called stage 1 hypertension (doctors often call high blood pressure ‘hypertension’). Your doctor will probably offer you drug treatment, as well as lifestyle advice. However, if you’re older (say, over age 60) your doctor may not recommend drug treatment unless your systolic pressure climbs to 150 or above.

Blood pressure from 160 to 179 (systolic) or 100 to 109 (diastolic)

This is sometimes called stage 2 hypertension. Your doctor will probably offer you treatment with more than one drug, as well as lifestyle advice.

Blood pressure at or above 180 (systolic) or 110 (diastolic)

This is called severe hypertension. Your doctor will probably offer you treatment with more than one drug, as well as lifestyle advice. Occasionally people with severe hypertension will need emergency treatment in hospital.