Blood pressure is the force of blood pushing against the walls of the arteries as the heart pumps it around the body.
We need enough pressure to deliver oxygen and nutrients to our organs, but pressure that stays too high can gradually cause serious damage.
High blood pressure, also called hypertension, is extremely common. According to the World Health Organization, it affects more than one billion adults worldwide and is a major cause of early death.
The condition can be especially dangerous because most people with high blood pressure feel completely normal. It may quietly damage the arteries, heart, brain, kidneys and eyes for years before a person realizes there is a problem.
That is why hypertension is often called a “silent killer.” Regular blood pressure checks are important because measuring it is usually the only way to know whether it is too high.
Blood pressure is recorded using two numbers, such as 120/80 mmHg. The first number shows the pressure when the heart contracts, while the second shows the pressure when the heart relaxes between beats.
A single high reading does not always mean someone has long-term hypertension. Stress, pain, exercise, caffeine and other factors can temporarily raise blood pressure, so doctors usually consider repeated measurements when diagnosing the condition.
However, extremely high blood pressure can sometimes become an emergency. A reading of 180/120 mmHg or higher is considered severely elevated and requires prompt attention, especially when symptoms or signs of organ damage are present.
Doctors distinguish between severely high blood pressure without immediate organ damage and a hypertensive emergency, in which the high pressure is actively harming organs. A hypertensive emergency requires immediate hospital treatment.
A severe headache can sometimes occur when blood pressure reaches dangerous levels. Other possible warning signs include confusion, weakness, numbness, difficulty speaking or seizures, which may indicate that the brain is being affected.
Chest pain is another serious warning sign because it can signal a heart attack or damage to the body’s largest artery. Severe high blood pressure can also place enormous strain on the heart and contribute to sudden heart failure.
Some people develop shortness of breath because fluid builds up in the lungs. Changes in vision can also occur if very high blood pressure damages blood vessels in the eyes or affects areas of the brain involved in sight.
Nausea, vomiting or a sudden feeling that something is seriously wrong may accompany a hypertensive emergency. Nosebleeds can occur in people with high blood pressure, but they are not by themselves a reliable sign that blood pressure has reached a dangerous level.
Anyone who has a blood pressure reading of 180/120 mmHg or higher together with symptoms such as chest pain, severe shortness of breath, weakness, confusion or major vision changes should seek emergency medical care. Waiting for the pressure to fall on its own could allow permanent organ damage to develop.
People who record a very high reading but have no concerning symptoms should still contact a healthcare professional promptly for advice. They should not take extra doses of blood pressure medicine unless a clinician has specifically told them to do so.
Fortunately, high blood pressure can often be controlled before it reaches this stage. Regular exercise, a balanced diet, reducing excess salt, maintaining a healthy weight, limiting alcohol and avoiding smoking can all support healthier blood pressure.
Many people also need prescription medicine, and taking it consistently is important even when they feel well. Suddenly stopping some blood pressure medicines can cause the pressure to rise sharply and may create additional health risks.
Guidance on recognising and treating dangerously high blood pressure is published by major medical organizations, including the American Heart Association and professional hypertension societies. Their recommendations emphasize both regular monitoring and urgent medical assessment when extremely high readings occur with signs of organ damage.
Because ordinary hypertension usually has no warning signs, prevention begins long before an emergency happens. Knowing your blood pressure, following treatment and recognizing genuine emergency symptoms can help protect the heart, brain, kidneys and eyesight for years to come.
If you care about high blood pressure, please read studies about what to eat and to avoid for high blood pressure, and 12 foods that lower blood pressure.
For more health information, please see recent studies about the connection between potato and high blood pressure, and how to eat your way to healthy blood pressure.
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