Fainting (Syncope)

Dr. Nadheer K M (AIIMS)MBBS

December 01, 2018

March 06, 2020


What is fainting?

Fainting, medically also known as syncope, is a medical condition where the patient undergoes a temporary loss of consciousness. Common in occurrence, it may be caused due to different reasons. In most cases, fainting is indicative of an underlying medical condition and therefore, should not be taken lightly. 

Reduce blood flow to the brain is the basic reason for fainting which lasts for merely a few seconds. This interrupted blood flow can be due to different reasons. Fortunately, it is for a short time and in most cases, it is not dangerous, however, it may suggest an underlying condition that could be life-threatening.

What are its associated signs and symptoms?

Common signs and symptoms associated with fainting include:

What are its main causes?

As outlined above, the hindered flow of blood to the brain is a major cause for fainting. This hindered blood flow can be due to different reasons. Some of these are:

  • Inability of the heart to pump blood due to a heart attack, heart failure
  • Lack of oxygen to the brain due to a stroke
  • Lack of enough blood or fluid to be pumped (dehydration, severe diarrhoea)
  • Lack of tone in the blood vessels to deliver blood to the brain

Other common triggers for fainting are:

  • Persistent exposure to excessive heat
  • Excess stress or strain
  • Weakness or lack of blood
  • Dehydration
  • Excessive consumption of alcohol
  • Low blood sugar due to skipping breakfast

How is it diagnosed and treated?

Fainting is a prominent and common symptom of several medical conditions and it does not require a test for diagnosis. However, upon fainting, if the patient is taken to the doctor, the doctor will examine the patient’s health and identify the potential reason for fainting.

In order to prevent the recurrence of fainting episodes, it is important to outline the underlying cause.

The doctor may suggest you to undergo certain tests to check for the proper functioning of the body. These may include;

  • An electrocardiogram (ECG) to check for the activity of the heart
  • Blood tests to assess anaemia
  • Blood test to check for diabetes or infection, hormonal disorders, and more
  • An X-ray of the skull or a CT scan too might be needed

Treatment depends on the underlying cause. While most often fainting might last for just a few seconds, fainting that lasts longer or recurs needs to be addressed urgently. Treatment varies dramatically based on the cause- be it dietary changes, controlling heart disease and diabetes, etc.


  1. American Academy of Family Physicians [Internet]. Leawood (KS); Syncope: Evaluation and Differential Diagnosis
  2. MedlinePlus Medical Encyclopedia: US National Library of Medicine; Fainting
  3. National institute of neurological disorders and stroke [internet]. US Department of Health and Human Services; Syncope Information Page
  4. Center for Disease Control and Prevention [internet], Atlanta (GA): US Department of Health and Human Services; Fainting (Syncope)
  5. Better health channel. Department of Health and Human Services [internet]. State government of Victoria; Fainting

Medicines for Fainting (Syncope)

Medicines listed below are available for Fainting (Syncope). Please note that you should not take any medicines without doctor consultation. Taking any medicine without doctor's consultation can cause serious problems.

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