What is a normal blood pressure?
As a general guide for adults, around 120/80 is ideal, and a clinic reading of 140/90 or above (or a home/ambulatory average of 135/85 or above) is usually considered high (hypertension). Low readings are common and often harmless unless they cause symptoms such as dizziness.
A single high reading does not diagnose high blood pressure — pressure varies through the day and rises with stress, pain and activity, so it is usually confirmed with repeated or home measurements.
Why do clinic and home readings differ?
Some people have higher readings at the surgery than at home ('white-coat' effect); others have the reverse. Because of this, home or 24-hour (ambulatory) monitoring is often used to get a truer picture before starting treatment.
If your pressure is high, your doctor will also look at your overall cardiovascular risk and may suggest lifestyle changes and, if needed, medication.
Common questions
Which number matters more?
Both matter, but in people over about 50 the systolic (top) number is usually the more important predictor of risk. Your doctor interprets them together with your age and other factors.
Is a high reading at the GP a problem?
Not on its own. It should be confirmed with repeated clinic readings or home/ambulatory monitoring before any diagnosis, because pressure naturally varies.
Related tools
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