The signs and symptoms of orthostatic hypotension and neurally mediated hypotension (NMH) are similar. They include:
Dizziness or light-headedness
Blurry vision
Confusion
Weakness
Fatigue (feeling tired)
Nausea (feeling sick to your stomach)
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. 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 NMH occur after standing for a long time or in response to an unpleasant, upsetting, or scary situation. The drop in blood pressure with NMH doesn't last long and often goes away after sitting down.