Low blood pressure, also known as hypotension, does not always cause symptoms. However, some people may experience symptoms such as dizziness, fainting, light-headedness, blurred vision, palpitations, confusion, nausea, and general weakness. These symptoms may occur when there is not enough blood flowing to the brain and other vital organs. If you have symptoms of extreme low blood pressure or shock, seek emergency medical help. Most healthcare providers consider blood pressure to be too low only if it causes noticeable signs and symptoms. Occasional minor dizziness or lightheadedness can be caused by many things, such as spending too much time in the sun or in a hot tub.