In people with recurrent vasovagal syncope, diagnostic accuracy can often be improved with one of the following diagnostic tests:

A tilt table test (results should be interpreted in the context of patients clinical presentations and with an understanding of the sensitivity and specificity of the test)
Implantation of an insertable loop recorder
A Holter monitor or event monitor
An echocardiogram
An electrophysiology study

Treatment
Treatment for reflex syncope focuses on avoidance of triggers, restoring blood flow to the brain during an impending episode, and measures that interrupt or prevent the pathophysiologic mechanism described above. Lifestyle changes
The cornerstone of treatment is avoidance of triggers known to cause syncope in that person. However, research has shown that people show great reductions in vasovagal syncope through exposure-based exercises with therapists if the trigger is mental or emotional, e.g., sight of blood. However, if the trigger is a specific drug, then avoidance is the only treatment. A technique known as "applied tension" may be additionally useful in those who have syncope with exposure to blood. The technique is done by tightening the skeletal muscles for about 15 seconds when the exposure occurs and then slowing releasing them. This is then repeated every 30 seconds for a few minutes. Because vasovagal syncope causes a decrease in blood pressure, relaxing the entire body as a mode of avoidance is not favorable. A person can move or cross their legs and tighten leg muscles to keep blood pressure from dropping so significantly before an injection.
The nucleus tractus solitarii of the brainstem is activated directly or indirectly by the triggering stimulus, resulting in simultaneous enhancement of parasympathetic nervous system (vagal) tone and withdrawal of sympathetic nervous system tone.This results in a spectrum of hemodynamic responses:

On one end of the spectrum is the cardioinhibitory response, characterized by a drop in heart rate (negative chronotropic effect) and in contractility (negative inotropic effect) leading to a decrease in cardiac output that is significant enough to result in a loss of consciousness. It is thought that this response results primarily from enhancement in parasympathetic tone. On the other end of the spectrum is the vasodepressor response, caused by a drop in blood pressure (to as low as 80/20) without much change in heart rate. This phenomenon occurs due to dilation of the blood vessels, probably as a result of withdrawal of sympathetic nervous system tone. The majority of people with vasovagal syncope have a mixed response somewhere between these two ends of the spectrum.One account for these physiological responses is the Bezold-Jarisch reflex. Vasovagal syncope may be part of an evolved response, specifically, the fight-or-flight response. Diagnosis
In addition to the mechanism described above, a number of other medical conditions may cause syncope. Making the correct diagnosis for loss of consciousness is difficult. The core of the diagnosis of vasovagal syncope rests upon a clear description of a typical pattern of triggers, symptoms, and time course.It is pertinent to differentiate lightheadedness, seizures, vertigo, and low blood sugar as other causes.