July 27, 2007 03:55:49 PM PST
-- Fainting occurs due to a sudden drop in blood flow to the brain, resulting in brief loss of consciousness. Fainting can be accompanied by dizziness or nausea.
Here are some common triggers, courtesy of the U.S. National Library of Medicine:
Straining during urination or a bowel movement.
Standing for too long in the same position, or quickly standing up from a lying position.
Severe pain, stress, fear or emotional distress.
Excessive bleeding or dehydration.
Medications used to treat conditions like high blood pressure, anxiety, allergies and nasal congestion.
Use of drugs or alcohol.
Low blood sugar.