Fainting
Educational information. Individual clinical review of this presentation by Dr. Ehsan is not yet documented. It does not replace personal medical evaluation.
Source: MedlinePlus, National Library of Medicine. Read the original source
MedlinePlus data edition September 26, 2026. Imported September 27, 2026. These dates do not indicate a new clinical review of the article.
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.
Symptoms, tests and care options
Further reading selected by MedlinePlus. Links open the original organizations’ websites.
- Fainting: First Aid · Mayo Foundation for Medical Education and Research
- Tilt Table Test · Mayo Foundation for Medical Education and Research
- Vasovagal Syncope (Diagnosis and Treatment) · Mayo Foundation for Medical Education and Research
- Vasovagal Syncope (Symptoms and Causes) · Mayo Foundation for Medical Education and Research
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For a life-threatening emergency, call 911 in the U.S. or your local emergency number.
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