The diagnosis commonly given when someone does have hypo-tension is hypovolemia low blood volume. There are many reasons as to why this could occur. More often than not it is due to an individual's nervous system. The brain has a difficult time monitoring that particular part of the body system. Usually it is a side effect from medications one could be taking at the time. Orthostatic hypo-tension is also known as postural hypo-tension, just as it sounds it has to do with your body's position. When your body has been in one position for a long time, then all of a sudden you make a big movement, not only does gravity kick in but your body has to compensate for that pressure change. Omron BP785 can confirm this. Similar to be deep in the sea, the human body cannot counterbalance for that quick change. Some people may experience dizziness or light headaches. Except those do not go away after the sudden movement. These could also be side effects from medications.
Postprandial Hypotension is another less common form of hypo-tension. It is due to not literally having enough blood to go around. Usually it occurs after someone has eaten, usually about sixty to seventy five minutes after eating. What happens is that the brain sends gush of blood to the stomach to aid in digestion, that sudden surge causes the rest of the body to lose out in a sense. Those same symptoms of dizziness, light headaches etc occur.