Fainting is a brief episode of unconsciousness caused by a sudden drop in blood pressure. The most likely cause of this sudden drop will either be some change in the blood vessels or the heartbeat itself. Blood vessels continually adjust their width to ensure a constant blood pressure. For instance, the vessels constrict tighten when we stand up to counteract the effects of gravity. Temporary low blood pressure can be caused by various events that prompt blood vessels to dilate expand , including extreme heat, emotional distress or pain. The lack of blood to the brain causes loss of consciousness. Usually, a fainting episode will only last a few seconds, although it will make the person feel unwell and recovery may take several minutes.
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When to Call for Fainting
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How common is fainting?
Fainting is pretty common in teens. The good news is that most of the time it's not a sign of something serious. Fainting is a temporary loss of consciousness. It happens when there isn't enough blood going to the brain because of a drop in blood pressure.
Fainting is usually caused by changes in circulatory and nervous systems that cause a drop in the amount of blood, sugar or oxygen that reaches the brain. An interrupted blood supply to the brain causes the person to lose consciousness and they fall to the floor. Sometimes, people may faint without warning. However, there are some signs to look out for which can indicate that a person is experiencing symptoms which might result in them fainting. These include:. If you or someone you are with feels faint, you should squat, sit, or lie down immediately. If sitting, place the head between the knees.