A hypertensive crisis is when blood pressure rises quickly and severely with readings of 180/120 mm Hg or greater. There are two types of hypertensive crises: hypertensive urgency and hypertensive emergency. Hypertensive urgency is when blood pressure is 180/120 or greater, but there are no signs of organ damage. In this case, it is recommended to wait about five minutes and try again to take a reading. If the second reading is just as high and there are no other associated symptoms of target organ damage such as chest pain, shortness of breath, back pain, numbness/weakness, change in vision or difficulty speaking, this would be considered hypertensive urgency. In this situation, healthcare professionals may just have the patient adjust or add medications, but this situation rarely requires hospitalization.

On the other hand, hypertensive emergency is when blood pressure is 180/120 or greater and there are signs of organ damage. In this case, it is recommended to call 911 or go to the emergency room immediately. Signs of organ damage may include stroke, loss of consciousness, memory loss, heart attack, damage to the eyes and kidneys, loss of kidney function, aortic dissection, angina (unstable chest pain), pulmonary edema (fluid backup in the lungs), and eclampsia.

It is important to note that pregnant women should contact their healthcare provider if their blood pressure is 140/90 or higher, and children with a blood pressure reading of 180/120 or greater should also seek medical attention.