Understanding Fainting (Syncope): Causes, Symptoms & When to See a Doctor

Syncope: Transient Loss of Consciousness

Fainting = brief loss of consciousness due to cerebral hypoperfusion. Affects ~3% annually.

Major Etiologies

• Cardiac: Arrhythmias, structural disease, outflow obstruction.
• Reflex (Neurally Mediated): Vasovagal, situational, carotid sinus.
• Orthostatic Hypotension: Volume depletion, autonomic failure, medications.
• Neurologic: Seizures, TIA (rarely pure syncope).
• Other: Anemia, hypoglycemia, pulmonary embolism.

When to Seek Care

• Recurrent episodes.
• Exertional syncope.
• Associated chest pain, palpitations, dyspnea.
• Family history of sudden cardiac death.
• Abnormal ECG or cardiac exam.

Initial workup: history, physical, ECG, orthostatic vitals. Further testing guided by suspicion.