Terminology describing high blood pressure emergencies can be confusing— high blood pressure crisis, malignant high blood pressure, high blood pressure urgency, and accelerated high blood pressure are all used. The diagnosis of a high blood pressure emergency is not only based on the absolute level of blood pressure, but also on an individual’s prior regular level of blood pressure. These emergencies seem to occur most commonly among patients who have not been diagnosed or have not followed a prescribed medication regimen.

However, severe high blood pressure can also occur in those who take medications as directed. In case of a high blood pressure emergency, the blood pressure should be lowered slowly with one or more medications. It is important not to lower blood pressure too abruptly, as rapid reductions in blood pressure may precipitate damage to the heart, brain, or kidneys.