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    • Services and providers for Fainting in the U.S.
  • National Institutes of Health

Also called: Syncope

If you've ever fainted, you are not alone - at least one third of people faint sometime in their lives. Fainting is a temporary loss of consciousness. You lose muscle control at the same time, and may fall down. Most people recover quickly and completely.

Fainting usually happens when your blood pressure drops suddenly, causing a decrease in blood flow to your brain. This is more common in older people. Some causes of fainting include

  • Heat or dehydration
  • Emotional distress
  • Standing up too quickly
  • Certain medicines
  • Drop in blood sugar
  • Heart problems

Fainting is usually nothing to worry about, but it can sometimes be a sign of a serious problem. If you faint, it's important to see your health care provider and find out why it happened.

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