Fainting: Common Causes, First Aid & When to Worry

What Is Fainting?

Fainting (syncope) is a temporary loss of consciousness caused by a brief drop in blood flow to the brain. It is common, affecting about one-third of people at some point. Most fainting is not serious, but it can result in injury from falling and sometimes signals an underlying heart or neurological condition.

Common Causes of Fainting

• Standing up too quickly (vasovagal)
• Dehydration
• Emotional stress or pain
• Overheating
• Low blood sugar
• Heart rhythm problems

When to See a Doctor

See a doctor after any fainting episode, especially if it happens during exercise, while lying down, or without warning. Seek emergency care if fainting is accompanied by chest pain, irregular heartbeat, or if you were injured.

Warning Signs That Need Immediate Attention

Frequently Asked Questions

What causes fainting?

The most common cause is vasovagal syncope, triggered by standing too long, heat, pain, or emotional stress. Other causes include dehydration, low blood sugar, heart rhythm problems, and neurological conditions.

When is fainting a sign of a heart problem?

Fainting during exercise, while lying down, or without warning could indicate a heart rhythm problem. Fainting with chest pain or palpitations also suggests cardiac involvement. These situations need prompt cardiologist evaluation.

What should I do if someone faints?

Lay them on their back and elevate their legs. Loosen tight clothing. Check breathing and pulse. If they don't regain consciousness within a minute, call 911. When they wake up, have them stay down for several minutes.

How do I prevent fainting?

Stay hydrated, avoid prolonged standing, rise slowly from sitting or lying positions, and eat regular meals. If you feel faint, sit or lie down immediately, squeeze your legs together, or squat to increase blood flow to the brain.

How much does fainting evaluation cost?

An EKG costs $50-$300. A tilt table test costs $500-$2,000. A cardiologist visit costs $200-$500. Blood work costs $50-$200. OpenMyPro helps you find affordable diagnostic care.

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