Any blood pressure that is below the normal expected for an individual in a given environment. Hypotension is the opposite of hypertension (abnormally high blood pressure).

Hypotension is a relative term because the blood pressure normally varies greatly with activity, age, medications, and underlying medical conditions.

The symptoms of low blood pressure include lightheadedness, dizziness, and fainting. These symptoms are most prominent when individuals go from the lying or sitting position to the standing position (orthostatic hypotension).

More Info: www.medicinenet.com