Fainting Can Happen For Many Reasons, But Unexplained Fainting May Signal Heart Trouble

Showbiz star Marie Osmond famously fainted during an appearance on the ABC series "Dancing With the Stars."

Former U.S. Attorney General Janet Reno, too, has fainted, as did Akshay Buddiga, a 13-year-old participant in the Scripps Howard National Spelling Bee contest.

We've all seen videos posted on the Internet of people fainting in school, in competitions or even during their own weddings.

Fainting is common, and can happen for many reasons – including after a scare or because of low blood sugar, but unexplained fainting can also signal a serious heart problem. Frequent or unexplained fainting warrants a trip to the doctor or emergency room.

VIDEO: Dr. Richard Besser explains some of the potential dangers of fainting.Play

Here are some tips on what you can do if someone near you faints.

• Check for a pulse, and call 911 if necessary.

• If the person is stable, raise their legs above their heart. This should send blood from their extremities back toward the brain.

If you feel faint, here are some other tips:

• Lie down and lift up your legs.

• If you cannot lie down, sit down and put your head between your knees until you feel better.

• Drink fluids to prevent dehydration.

• Don't stand up quickly.

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