High blood pressure occurs when the pressure of blood in the body is too high, putting extra strain on the blood vessels.

High blood pressure, otherwise known as hypertension, is dangerous as it can cause heart attacks and strokes.

According to the NHS, more than one in four adults in the UK have high blood pressure, many of whom don’t actually realise it.

This is because the condition rarely has noticeable symptoms.

However, in some cases, people with very high blood pressure could experience chest pain.

If symptoms of high blood pressure do occur, it is usually because patients are experiencing a ‘crisis’ due to their blood pressure reaching dangerously high levels.

Other symptoms which could occur in this situation include vision problems, tiredness, headaches, nausea and vomiting.

These symptoms will usually only occur in the case of malignant hypertension, otherwise known as a hypertensive crisis.

A hypertensive crisis is when blood pressure is extremely high.

Normal blood pressure is considered to be between 90/60mmHg and 120/80mmHg, according to the NHS.

High blood pressure is considered to be 140/90mmHg or higher.

Malignant hypertension is considered to be above 180/120mmHg and should be treated as a medical emergency as it can cause organ damage – usually to the kidneys or eyes.

Malignant hypertension develops rapidly and is often a result of high blood pressure not being controlled properly.

For example, if you are taking medication for high blood pressure but miss doses, you could be at risk of developing an hypertensive crisis.

In rare cases, malignant hypertension can cause swelling of the brain, which can lead to a dangerous condition called hypertensive encephalopathy.

Symptoms of this include: blindness, changes in mental status, coma, confusion, drowsiness, worsening headaches, nausea and vomiting, and seizures.

Aside from hypertensive crises, headaches and chest pain can also appear when people experience a sudden increase in high blood pressure, which is known as accelerated hypertension.

“Patients who experience early signs of hypertension usually complain about dull headaches, short moments of lightheadedness as well as unusually frequent nosebleeds,” said medical website Zava.

“It is quite rare for blood pressure to cause symptoms in the early stages of the condition.”

As high blood pressure in general rarely has symptoms, the NHS advises getting blood pressure checked regularly by a GP.