Fainting (syncope) is a suddenloss of consciousnessfrom a lack of blood flow to the brain.
This article explains the symptoms of fainting and many possible reasons why it can happen.
It details diagnosis and treatment options, and offers some tips on how fainting may be prevented.
Illustration by Joshua Seong for Verywell Health
Most people will suddenly feel flushed and warm, become weak, and lose consciousness.
This can have a number of causes, including pain or stress.
During aheart attack, the heart muscle can become too weak to maintain blood pressure.
There are many causes of dehydration, including vomiting or diarrhea.
Vomiting and diarrhea, specifically, are related to vagus nerve function.
People with shock will most likely become confused, and then lose consciousness as their condition gets worse.
Illicit Drugs or Alcohol
Alcoholmisuse andsubstance abusecan cause people to pass out.
Besides its obvious sedation effect, alcohol makes people urinate, which will eventually lead to dehydration.
It also dilates blood vessels, which decreases blood pressure.
It is possible to die fromalcohol poisoning, and passing out is a sign of serious intoxication.
It has several potential causes, including Parkinson’s disease.
Some people (commonly males) can pass out when they urinate (micturitionsyncope).
But some other causes are unique to kids, like holding their breath during temper tantrums.
Headaches and bloodshot eyes are common in kids playing these potentially fatal games.
If you see someone pass out, see to it the person is breathing.
If not, call 911 and beginCPR.
When to See a Healthcare Provider
By itself, fainting is not life-threatening.
However, some dangerous conditions can cause people to faint and they should be evaluated by a healthcare provider.
If someone faints but doesn’t wake up within a few seconds, seek medical care.
Your healthcare provider can diagnose the cause of passing out (or feeling like you will) while pregnant.
Diagnosis and Treatment
Treatment for a condition that causes fainting will depend on the underlying cause.
Your healthcare provider will rely on a full medical history and physical assessment.
They also may order tests that include anelectrocardiogram(12-lead EKG) to check heart rhythm.
You may need blood work, glucose testing, or other assessments.
You also may need further evaluation and specialist care, depending on the results.
Treatment will be determined by the diagnosis and can range from simplestress management techniquesto cardiac surgery and rehabilitation.
What Is a Tilt Table Test?
The table is used to change your body’s positions and watch the heart rate and other responses.
Summary
Fainting is a sudden loss of consciousness from a lack of blood flow to the brain.
People who have experienced multiple fainting spells should see a healthcare provider to learn the cause.
Certain tests, like a tilt table test, can help with diagnosis and treatment of syncope.
Frequently Asked Questions
Yes, it can.
Find ways to distract yourself.
Also, let the phlebotomist know if you’re prone to fainting.
They may be able to let you lie down during the test.
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