The signs and symptoms of orthostatic hypotension may happen within a few seconds or minutes of standing up after you’ve been sitting or lying down. You may feel that you’re going to faint, or you may actually faint. Signs and symptoms include:
These signs and symptoms go away if you sit or lie down for a few minutes until your blood pressure adjusts to normal.
The signs and symptoms of neurally mediated hypotension (NMH) are similar to those of orthostatic hypotension. They occur after standing for a long time or in response to an unpleasant, upsetting, or scary experience. The drop in blood pressure with NMH doesn't last long and often goes away after sitting down.
In shock, not enough blood flows to the major organs, including the brain. The early signs and symptoms of reduced blood flow to the brain include lightheartedness, sleepiness, and confusion. In the earliest stages of shock, it may be hard to detect any signs or symptoms. In older people, the first symptom may only be confusion.
Over time, as shock worsens, a person won’t be able to sit up without passing out. If the shock continues, the person will lose consciousness. Shock is often fatal if not treated right away.
Other signs and symptoms of shock vary, depending on what’s causing the shock. When low blood volume (from major blood loss, for example) or poor pumping action in the heart (from heart failure, for example) causes shock:
When extreme widening or stretching of blood vessels (such as in septic shock) causes shock, a person feels warm and flushed at first. Later, the skin becomes cold and clammy, and the person feels very sleepy.
Shock is an emergency and must be treated right away.