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Fainting
URL of this page: https://medlineplus.gov/fainting.html

Fainting

Also called: Syncope

Summary

Fainting is a temporary loss of consciousness. If you're about to faint, you'll feel dizzy, lightheaded, or nauseous. Your field of vision may "white out" or "black out." Your skin may be cold and clammy. You lose muscle control at the same time, and may fall down.

Fainting usually happens when your blood pressure drops suddenly, causing a decrease in blood flow to your brain. It 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

When someone faints, make sure that the airway is clear and check for breathing. The person should stay lying down for 10-15 minutes. Most people recover completely. 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.

Start Here

  • Fainting (American Academy of Family Physicians) Also in Spanish
  • Syncope From the National Institutes of Health (National Institute of Neurological Disorders and Stroke)

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Journal Articles References and abstracts from MEDLINE/PubMed (National Library of Medicine)

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The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health.