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.
Most doctors consider chronically low blood pressure too low only if it causes noticeable symptoms. Some experts define low blood pressure as readings lower than 90 mm Hg systolic or 60 mm Hg diastolic â you need to have only one number in the low range for your blood pressure to be considered lower than normal.