Lightheadedness makes you feel as though you are about to faint or
pass out. Symptoms usually improve or go away if you lie down for a few
moments.
Lightheadedness usually is not serious. It is common to feel
lightheaded occasionally. However, when persistent lightheadedness keeps you
from completing your normal daily activities, an evaluation by a health
professional usually is needed.
A serious cause of lightheadedness is bleeding. Most of the time when
bleeding is present, the need to seek medical care is obvious. However,
sometimes bleeding is not obvious (occult bleeding). Small amounts of bleeding
may occur over days or weeks without being noticed. When this is the case,
lightheadedness and fatigue may be the first noticeable symptoms of blood loss.
If you have new lightheadedness, look for signs of bleeding, such as:
- Rectal bleeding or blood in the
stool.
- Heavy or prolonged vaginal bleeding. This bleeding is
more serious if you:
- Have new lightheadedness or feel as if you
may pass out.
- Have repeated dizziness, lightheadedness, or fainting
that occurs when you sit up or stand up.
- Pass several blood clots
that are larger than a quarter.
- Bloody or pink urine (hematuria). Blood in the
urine may only show up when you look at a urine sample with a
microscope.
- Increase in the number and severity of bruises (purpura).
- Several unexplained
nosebleeds.
If lightheadedness and fainting (syncope) occur
every time you stand up, blood loss or fluid loss may be the cause. Persistent
lightheadedness and fainting requires evaluation by a health
professional.