Fainting & Unconsciousness
Signs & Symptoms
Fainting is a brief loss of consciousness. It can last from seconds to 30 minutes. Just before fainting, a person may feel a sense of dread, feel dizzy, see spots, and have nausea.
If a person falls and can't remember the fall itself, he or she has fainted.
An unconscious person is hard to rouse and can't be made aware of his or her surroundings. The person is unable to move on his or her own.
Fainting is due to a sudden drop in blood flow or glucose supply to the brain. This causes a temporary drop in blood pressure and pulse rate. Medical reasons for this include:
Low blood sugar (hypoglycemia). This can occur in diabetics, in early pregnancy, in persons on severe diets, etc.
Anemia. Eating disorders.
Conditions which cause rapid loss of blood.
Abnormal heart rhythm. Heart attack. Stroke.
Head injury. Heat stroke. Heat exhaustion.