Fainting is a short-term loss of consciousness that occurs due to reversible disorders in brain functions. The most common cause of fainting is decreased blood flow from the heart, hypotension, or decreased blood flow in the brain due to occlusions in the cerebral arteries. Sometimes, a decrease in brain activity or deterioration in brain metabolism due to systemic diseases can also cause this.

Fainting is a short-term loss of consciousness that occurs due to reversible disorders in brain functions. The most common cause of fainting is decreased blood flow from the heart, hypotension, or decreased blood flow in the brain due to occlusions in the cerebral arteries. Sometimes, a decrease in brain activity or deterioration in brain metabolism due to systemic diseases can also cause this.

Difference between fainting and epileptic seizures

While fainting usually starts slowly, the epileptic seizure starts suddenly. No aura develops before fainting, but there is an aura period before epilepsy. These are the warning symptoms of fainting. While fainting lasts short, epileptic seizures last longer. Fainting usually occurs when standing or standing up, but an epileptic seizure can occur in any position. While convulsions are rare in fainting, convulsions occur frequently in epileptic seizures. The tongue is not bitten during fainting, but it is common to bite the tongue in epileptic seizures. Headache does not occur before or during fainting. Headache, lethargy, or confusion are common in epileptic seizures.

The most common causes of fainting are:

  • Simple fainting (Vazovagal or vasodepressor syncope) (Hypotension is the main cause. It can also start with pain, fear or anxiety. Excessive alcohol consumption, being in a confined environment, extreme heat can also cause it. The patient usually sits or stands. Usually occurs in young people. Before fainting sensation of warmth, nausea, abdominal pain or spasm, drowsiness, pallor, sweating, cold feeling in hands and feet, and fainting. Heart rate increased. Patient recovers quickly in supine position)
  • Cardiac syncope (Structural disorders of the heart or arrhythmias may cause this. There has been a decrease in the amount of blood coming out of the heart. )
    • Severe aortic stenosis (usually fainting on exertion)
    • Pulmonary arterial hypertension (Syncope is triggered by exertion.)
    • Idiopathic hypertrophic subaortic stenosis (syncope occurs after exercise)
    • Sick sinus syndrome (It occurs especially in the elderly due to sinus bradycardia)
    • Pacemaker dysfunction
    • Sinus node dysfunction
    • Wolf Parkinson White syndrome
    • LGL syndrome
    • cardiomyopathy
    • Mitral valve prolapse
    • long QT interval syndrome
    • Medicines
    • metabolic disorders
  • Vascular syncope
    • Orthostatic syncope (Sudden hypotension develops and syncope occurs while sitting or standing. It occurs more frequently in those who stay in an upright position for a long time.)
    • Cerebrovascular syncope (This is the least common form of syncope. Generally, the deterioration of blood supply as a result of narrowing or blockage in the brain vessels causes syncope.
  • Other causes of syncope
    • Carotid sinus syndrome (It is rare. Hypotension develops even though the heart rate is normal.)
    • Glossopharyngeal neuralgia (characterized by sore throat, slowed heart rate, hypotension and syncope.)
    • Vomiting syncope (It is common in old men. It usually occurs at night. The patient faints while peeing or after urinating.)
    • Cough syncope (Usually obese men with chronic obstructive pulmonary disease may develop syncope after severe coughing.)
    • Hysterical fainting (It is seen in neurotic young people and rarely in women. The patient faints in the presence of others. It develops suddenly. It is usually involuntary. Sometimes the patient may faint voluntarily. The patient does not have any other symptoms.)
    • Hypoglycemic syncope (It usually occurs as a result of low blood sugar in diabetic patients receiving oral hypoglycemic therapy. It improves with sugar intake.)
    • Hyperventilation (Frequent and excessive breathing may cause tingling, numbness, chills, dizziness, convulsions and syncope in the patient.)
    • Reflex cardiac asystole (rare)
  • Combined causes of syncope (Especially in the elderly, more than one cause may coexist as a cause of syncope)

Although the cause of syncope is known and is insignificant in rare cases, patients with an underlying disease and recurrent syncope should definitely be analyzed for the cause and evaluated for treatment.

The causes of syncope should be investigated in patients who do not recover for a long time after fainting.