A hypertensive crisis is a severe increase in blood pressure that can lead to a stroke. Extremely high blood pressure — a top number (systolic pressure) of 180 millimeters of mercury (mm Hg) or higher or a bottom number (diastolic pressure) of 120 mm Hg or higher — can damage blood vessels. The blood vessels become inflamed and may leak fluid or blood. As a result, the heart may not be able to pump blood effectively.

Causes of a hypertensive emergency include:

• Forgetting to take your blood pressure medication
• Stroke
• Heart attack
• Heart failure
• Kidney failure
• Rupture of your body's main artery (aorta)
• Interaction between medications
• Convulsions during pregnancy (eclampsia)

A hypertensive crisis is divided into two categories: urgent and emergency. In an urgent hypertensive crisis, your blood pressure is extremely high, but your doctor doesn't suspect you have any damage to your organs.

In an emergency hypertensive crisis, your blood pressure is extremely high and has caused damage to your organs. An emergency hypertensive crisis can be associated with life-threatening complications.

Signs and symptoms of a hypertensive crisis that may be life-threatening may include:

• Severe chest pain
• Severe headache, accompanied by confusion and blurred vision
• Nausea and vomiting
• Severe anxiety
• Shortness of breath
• Seizures
• Unresponsiveness

If you experience a severe increase in your blood pressure, seek immediate medical attention. Treatment for hypertensive crisis may include hospitalization for treatment with oral or intravenous medications.