Vasovagal Syncope – Symptoms and Causes
Overview
Vasovagal syncope happens when a person faints due to their body’s overreaction to specific triggers. Common triggers include seeing blood or experiencing intense emotional stress. This condition is also known as neurocardiogenic syncope.
During an episode, the person’s heart rate and blood pressure suddenly decrease. This reduction causes less blood to flow to the brain, resulting in a brief loss of consciousness.
Most cases of vasovagal syncope are harmless and don’t require treatment. The main concern with vasovagal syncope is preventing injuries that might occur during fainting episodes.
Signs and Symptoms
Before fainting happens, your body often gives warning signals. You might notice your skin color changing. Some people feel dizzy or experience tunnel vision, where they can only see what’s directly in front of them.
You might also have an upset stomach, feel unusually warm, or break out in a cold, clammy sweat. Many people report their vision becoming blurry just before they faint.
If someone is watching when you faint, they might notice:
- Jerky body movements
- Weak, slow pulse
- Enlarged pupils
Most people start to recover within one minute after fainting. Be careful not to stand up too quickly afterward. Standing within 15โ30 minutes after fainting increases your risk of fainting again.
When Medical Help Is Needed
Fainting sometimes points to serious health problems with your heart or brain. It’s important to talk to a healthcare provider after you faint, especially if it’s your first time.
Causes
Vasovagal syncope happens when your nervous system overreacts to certain triggers. This reaction affects both your heart rate and blood pressure.
Common triggers include:
- Standing for extended periods
- Exposure to hot environments
- Viewing blood
- Having blood drawn
- Fear of injury
- Straining during bowel movements
Sometimes, vasovagal syncope can occur without any obvious trigger.
During an episode, two main things happen:
- Your heart rate slows down
- Blood vessels in your legs dilate (widen)
These changes cause blood to pool in your legs. As a result, your blood pressure drops sharply. When this happens, blood flow to your brain decreases quickly, leading to fainting.
Risk Factors
Vasovagal syncope is more common in certain groups of people:
- Children and young adults face higher risks, though it can occur at any age
- People who spend extended periods standing
These factors don’t guarantee someone will experience vasovagal syncope, but they do increase the likelihood of an episode.
Prevention
Preventing vasovagal syncope involves recognizing early warning signs and taking quick action. When you feel light-headed or think you might faint, take these immediate steps:
Quick Actions When Feeling Faint
- Lie down flat on your back
- Elevate your legs above heart level
- Stay in this position until symptoms pass
If lying down isn’t possible, sit and put your head between your knees. This position helps maintain blood flow to your brain.
Many people experience warning signs before fainting. Knowing these signals gives you time to react.
Common Warning Signs
- Dizziness or lightheadedness
- Nausea
- Cold, clammy skin
- Blurred vision
- Ringing in ears
- Feeling warm or hot suddenly
For those with recurring episodes, doctors may suggest preventive strategies. These might include:
- Drinking more water daily
- Increasing salt intake (if appropriate)
- Wearing compression stockings
- Avoiding known triggers
Learning your personal triggers is important. Common triggers include:
| Common Triggers | Prevention Strategies |
|---|---|
| Standing too long | Change positions regularly |
| Hot environments | Stay cool, dress in layers |
| Emotional stress | Practice calming techniques |
| Blood or injury sights | Look away, use distractions |
Some people benefit from physical counterpressure maneuvers. These involve tensing specific muscle groups when symptoms begin, to help maintain blood pressure.
