What Exactly Is a Fainting Spell—and When Should You Worry?

Most cases are benign but being attentive could save a life
What Exactly Is a Fainting Spell—and When Should You Worry?

Contributor: Peter Aziz, MD

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As scary as it may be, fainting – also known as syncope – is actually very common. It occurs in about one-third of the general population, and there are a number of different things that can cause someone to pass out.

It can start with a feeling of dizziness, followed by narrowed vision, muffled sense of hearing – until you wake up somewhere unexpected, like the floor, wondering what happened.

Syncope is defined as a temporary loss of consciousness and muscle control caused by low blood flow to the brain. To put it more simply, fainting can occur when your blood pressure or heart rate drops suddenly.

It is not considered a disease itself, but is rather a sign or a symptom that can potentially signify an underlying condition.

Although it’s rare, fainting can be a precursor of a life-threatening illness, like a heart disorder, which is why patients who suffer from this problem should be evaluated promptly by a physician.

When passing out isn’t a concern

The most common cause of fainting is what physicians term vasovagal syncope. This type of syncope is illustrated in the classic movie scene in which someone receives shocking news and passes out.

It happens as a result of a fascinating chain of reactions in the body. It can occur when your body overreacts to certain triggers, with changes in vessel tone and blood pressure, as mediated by the brain.

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These can include prolonged standing, dehydration, the sight of blood, emotional trauma, stress, having blood drawn, fear of bodily injury, straining – like having a bowel movement – and even hair combing.

These swooning signs provide comfort to doctors because often, they suggest the cause of fainting is nothing to worry about.

When vasovagal syncope is occurring, you will experience warning signals that include dizziness, headache, nausea, sweating, paleness, feeling warm or hot, and vision and/or auditory changes.

Although vasovagal syncope is typically harmless and requires no treatment, a physician may instruct a patient to increase his or her fluid and salt intake, and sit or lie flat if these symptoms occur.

When should I worry?

Fainting, when associated with exercise or exertion, should not be taken lightly. Typically in a benign fainting spell, a patient will have some recall just prior to passing out.

But when a patient has no memory of the event whatsoever, it can suggest than an arrhythmia was the culprit.

A thorough evaluation of fainting should include an electrocardiogram test, as well as a detailed examination of the patient’s family members, since family history can help provide deeper clues as to whether or not passing out is benign or a bigger problem.

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Physicians will often ask if anyone in the family experiences or has experienced passing out spells, seizures, sudden unexplained death (like drowning), single car accidents or heart attacks at a young age.

All these seemingly weird questions can suggest a life-threatening arrhythmia may run in the family.

When syncope is more a risk

During the summer when temperatures are hot, outdoor activities are more abundant and fainting can occur more frequently due to overheating and dehydration.

It’s important to stay vigilant and be prepared in case this happens to someone you know. Although benign fainting spells are brief and sufferers come back to their own within 10 to 15 seconds, they can still injure themselves during the event.

If you see someone faint, don’t just stand there. Check to see if they’re conscious, and if they’re not, call 911 immediately and start administering CPR.

Despite the fact that fainting is fairly common and most instances are benign, being attentive and aware of this topic – especially during the sizzling summer months – can potentially help save a life.

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