Transient loss of consciousness, typically lasting no longer than 1 to 2 minutes, due to a transient drop in cerebral perfusion pressure

General Prevention

  • Avoiding circumstances predisposing to the most common form of syncope (vasovagal)
  • Sitting or lying down when warning signs occur
  • Maintaining adequate hydration, especially during illness/exertion


Most common mechanism is vasovagal or neurocardiogenic, in which a variety of stimuli and conditions—pain, heat, dehydrated state, emotional upset, carotid pressure—trigger increased vagal tone, leading to slowed heart rate, peripheral vasodilation, and decreased cerebral perfusion.

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