Vasovagal Attack: Causes

What causes a vasovagal attack?

A vasovagal attack is caused by a rapid drop in blood pressure and heart rate, resulting in a decrease in blood flow to the brain. Standing for a prolonged period of time, situations that induce panic or fear, and strenuous exercise can also cause a vasovagal attack.

A vasovagal attack may also happen as the result of heat exposure as your body attempts to cool itself by circulating blood to your body’s periphery. It can also occur in an individual straining to have a bowel movement, due to stimulation of the vagus nerve.

What are the risk factors for vasovagal attack?

A number of factors increase the risk of having a vasovagal attack. Not all people with risk factors will have vasovagal attacks. Risk factors for vasovagal attacks include:

• Blood pooling in the legs and away from the brain (standing for a long period of time or after strenuous exercise)
• Exposure to blood or frightening stimuli (having blood drawn or seeing blood)
• Heat exposure
• Stimulation of the vagus nerve (while straining to have a bowel movement)

Reducing your risk of vasovagal attack

You may be able to lower your risk of vasovagal attacks by:

• Lying down and elevating your feet if a vasovagal attack is beginning
• Participating in stress reduction techniques or therapy to reduce your response to triggers
• Understanding the potential triggers for vasovagal attacks