Rethinking Seizure Care Blog

Similarities between Vasovagal Syncope (Fainting Spells) and Epilepsy

Posted by RSC Diagnostics on Mar 31, 2020

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Epileptic seizures are due to the misfiring of electrical impulses in the brain. This neurological disorder can result in convulsions, loss of consciousness, and limited motor activity. Vasovagal syncope can mimic epileptic seizures and be difficult to diagnose at first look.

There are about 3 million cases of vasovagal syncope in the United States per year. Vasovagal syncope is characterized by simple fainting spells. However, these fainting spells can be accompanied by confusion, jerking movements and loss of consciousness much like an epileptic seizure. At times, patients’ pupils may dilate and be noticed by others prior to fainting.

Typically, a patient will experience vasovagal syncope when a stress trigger is activated. This can be due to the sight of blood, having blood drawn, watching someone else have blood drawn or a procedure performed, heat exposure, standing for a prolonged period of time, straining, and fear.

What Are the Symptoms?

When confronted with one of these stress triggers, the patient may begin to experience lightheadedness, dizziness, tunnel vision, nausea, cold sweats, blurred vision, and loss of color (sudden paleness). Some patients report excessive yawning. These symptoms tend to come on quickly after exposure to a trigger.

The body reacts by slowing the heart rate and widening the blood vessels in the legs. This gives the body the ability to lower blood pressure by allowing the blood to collect in the legs. This reduces blood flow to the brain and the patient faints.

The patient usually begins to recover within one minute, but may need 15 to 30 minutes to rest before trying to stand again. If they stand too soon, they increase their risk of fainting again until the blood flow is rebalanced in the brain.

Notify Physician

It is critically important that patients notify their physician of any fainting spells as this can be the symptom of an underlying heart problem. The physician will want to run tests like an echocardiogram, electrocardiogram, stress test, and blood tests to rule out heart or brain disorders. At this point, physicians may be able to differentiate between the vasovagal syncope and an epileptic seizure.

Another effective test used to rule out epileptic seizures is the tilt table test. If the conclusions of the above tests do rule out heart conditions, the tilt table test may be performed. The test requires the patient to lie on their back on the table while the table changes position, tilting in various angles. The physician monitors the patient’s reactions including heart fluctuations and blood pressure changes.


If the physician diagnoses the episodes as vasovagal syncope and not epileptic seizures, medication is typically not necessary. The patient may be asked to avoid triggers to lower the risk of reoccurrence.

Vasovagal syncope is common and it is estimated that most people will experience a fainting spell at least once in their lives. One isolated incident is no call for alarm, but a physician should be notified to rule out any other issues.

However, if a patient is experiencing these spells on a consistent basis, a neurologist should be consulted. It is recommended the patient keep a detailed tracking sheet for the neurologist to review. This sheet should include when the fainting spell occurred, if a seizure accompanied loss of consciousness, and if there were any stress triggers present. The neurologist will need the detailed plan to help make an accurate assessment.




Mayo Clinic Health

Topics: Types of Seizures