Fainting (syncope)

Also known as: neurally mediated syncope, NMS, vasovagal syncope, vasodepressor syncope, reflex mediated syncope, neurocardiogenic syncope

What is Fainting (syncope)?

Syncope is the medical term for the sudden brief, temporary loss of consciousness that is also known as fainting. Up to 15% of children have fainting episodes.

What causes fainting (syncope)?

Syncope is caused by the relaxation of blood vessels causing a drop in blood pressure with less blood getting to the brain. Usually fainting is not a sign of serious  disease, however syncope can have both mild and serious causes. There are a wide variety of conditions that can lead to syncope, including changes in circulation or blood pressure, stress, heat exhaustion, coughing spells and certain medications. A number of medical conditions can cause syncope as a side effect.

What are the symptoms of fainting (syncope)?

Syncope is typically viewed as a symptom itself of other conditions. Prior to the loss of consciousness, a person may experience dizziness, lightheadedness, nausea, pale skin, sweating or vision problems.

What are fainting (syncope) care options?

Fainting merits a visit to the doctor, as it can be a sign of more serious medical conditions. A doctor can assess the potential causes of the fainting and choose appropriate care options based on those.


Reviewed by: Jack Wolfsdorf, MD, FAAP

This page was last updated on: July 24, 2020 04:48 PM

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