Hypertension (HTN or HT), also known as high blood pressure (HBP), is a long-term medical condition in which the blood pressure in the arteries is persistently elevated. A condition in which the force of the blood against the artery walls is too high.Usually hypertension is defined as blood pressure above 140/90, and is considered severe if the pressure is above 180/120.High blood pressure often has no symptoms. Over time, if untreated, it can cause health conditions, such as heart disease and stroke.Eating a healthier diet with less salt, exercising regularly and taking medication can help lower blood pressure.