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.
For example, people who exercise regularly often have lower blood pressure than people who are not as fit. But if your blood pressure drops suddenly or causes symptoms like dizziness or fainting, it is too low. It can cause shock. Shock can be dangerous if it is not treated right away. Blood pressure is a measure of how hard the blood pushes against the walls of your arteries as it moves through your body.