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Fainting

Fainting can be caused by a variety of things. It is related to your heart, circulation, blood pressure and breathing, but is triggered by different factors in different people. More than one thing may be the cause of fainting and sometimes a specific cause cannot be found.

Stressful situations, pain and excitement can all cause fainting. They cause feelings of strong emotion, distress or shock, which puts physical and mental strain on the body. Stressful situations may be anything from receiving an injection, to feeling panicky in a hot and overcrowded room. Fainting can also occur when you feel very nervous, or after witnessing a shocking or unexpected event.

Fainting occurs when there has been a fall in blood pressure, which reduces the amount of blood and oxygen flowing to the brain. This is more common in people with low blood pressure, teenagers, and pregnant women. A faint is most likely to happen in a hot environment when blood vessels in the skin expand, reducing central blood pressure.