- Fainting is sudden brief loss of consciousness with falling down
- A return to being awake and alert happens within 1 minute
- Also called passing out or blacking out
- Fainting is a brief loss of consciousness. Normal awareness returns in less than 1 minute if the person is allowed to lie down.
- If standing, the person falls to the ground.
- If sitting, the person slumps over.
- The medical name for fainting is syncope.
- Fainting happens in 15% of healthy teens. Simple fainting doesn't occur before age 6. It is not common before age 10.
- Causes: in teens, 98% is simple fainting. Less than 1% have heart problems. In older adults, serious causes are much more common.
- Cause of Simple Fainting: decreased blood flow to the brain.
- Risk Factors: mild dehydration, fasting, hot weather, lack of sleep, recent illness, change in altitude.
- Most fainting is harmless. There is a risk of a head or face injury from sudden falling.
Simple Fainting (Benign Fainting): Types
- Standing too long in one place before fainting is the most common type. The medical name is orthostatic or postural syncope. Happens at church, graduations, weddings or at events when standing a long time. More common if one keeps the knees "locked." This pools the blood in the leg veins. A person who stands long enough in one place will faint.
- Standing up quickly (often after lying down) before fainting is a less common cause. Often this just causes a person to feel dizzy for a short time. More common in the morning after not eating or drinking during the night.
- Sudden stressful feelings before fainting. This is called vasovagal syncope. Seeing a badly injured person or pet can trigger fainting. Other examples are seeing someone vomit, bleed or pass a stool. Also, stressful events such as speaking or performing in public can cause fainting.
- Sudden physical pain before fainting such as getting a shot or a blood test. Having slivers or stiches taken out can also trigger fainting. The stress of the event may cause the fainting rather than the pain itself.
Warning Signs For Simple Fainting
- Dizziness (light-headed), blurred vision, nausea, sweating, feeling cold.
- These last for 5 to 10 seconds before passing out.
- The person may look pale just before passing out.
Serious Causes of Fainting
- Cardiac syncope. Any fainting that happens during exercise needs a heart work-up. This cause is rare in children.
- Blood loss - large amount or bleeding inside the body
- Concussion or head injury
- Sudden drop in blood sugar. Mainly happens in people with diabetes.
- Drug or alcohol abuse