What is considered high blood pressure?

According to the American Heart Association, a patient is diagnosed with high blood pressure if the individual consistently has readings higher than 140/90 mm Hg. A reading of less than 120/80 mm Hg indicates that a patient has a normal, healthy level of blood pressure, notes the American Heart Association.

The American Heart Association reports that a systolic reading of 120 to 139 mm Hg, with or without a diastolic reading of 80 to 89 mm Hg, indicates prehypertension, a condition that can require medical attention. An individual must seek immediate medical care when a systolic reading exceeds 180 mm Hg or a diastolic reading rises above 110 mm Hg, warns the American Heart Association.