Neuron Structure. Your brain is made of approximately 100 billion nerve cells, called neurons. Neurons have the amazing ability to gather and transmit electrochemical signals -- think of them like the gates and wires in a computer.
Most doctors will only consider chronically low blood pressure as dangerous if it causes noticeable signs and symptoms, such as: 1  Dizziness or lightheadedness. 2  Nausea. 3  Fainting (syncope)  Dehydration and unusual 1  thirst. Dehydration can sometimes cause blood pressure to drop.  Lack of 1  concentration. Blurred vision.  Cold, clammy, pale skin.
Low Blood Pressure Can Be Dangerous With very few exceptions, chronic blood pressure below 120/80 is not dangerous. Low blood pressure is usually considered dangerous only when it causes the symptoms mentioned above or results from sudden blood pressure decreases. In cases where your blood pressure drops suddenly, it isnât actually the low blood pressure itself that causes the danger, but rather the sudden change from a higher value to a lower value. Sudden changes in blood pressure can cause interruptions in the blood supply to your heart, kidneys, and brain, and will almost always be accompanied by distinctive symptoms.