Ali, fainting is a scary event. There are many reasons that people faint. I researched this for all of us. I hope it helps.
Dew

Fainting is a temporary loss of consciousness that is spontaneously recovered after only a brief period of time. People faint because of a lack of blood flow and decreased oxygen to the brain. The cause of fainting can be related to a number of conditions or situations, some involving the heart, many not. The medical term for fainting is syncope (SIN-ko-pee).

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