Syncope: Facts, Causes, Symptoms & Treatment

fainting syncope


What is syncope?

Syncope is temporary loss of consciousness and posture, described as “fainting” or “passing out.” It’s usually related to temporary insufficient blood flow to the brain. It most often occurs when the blood pressure is too low (hypotension) and the heart doesn’t pump a normal supply of oxygen to the brain.

Syncope Facts

  • Being unconscious is not normal; those affected should seek medical care.
  • Syncope may be caused by a variety of mechanisms, but isn’t caused by head injury, which is considered a concussion.
  • Some causes of syncope can be a warning of a life-threatening situation. Most times, syncope is a relatively benign situation.
  • While most episodes of syncope can be easily explained, some patients never receive a diagnosis or know the specific cause.

What causes syncope?

It may be caused by emotional stress, pain, pooling of blood in the legs due to sudden changes in body position, overheating, dehydration, heavy sweating or exhaustion. Syncope may occur during violent coughing spells (especially in men) because of rapid changes in blood pressure. It also may result from several heart, neurologic, psychiatric, metabolic and lung disorders. And it may be a side effect of some medicines.

Some forms of syncope suggest a serious disorder:

  • those occurring with exercise
  • those associated with palpitations or irregularities of the heart
  • those associated with family history of recurrent syncope or sudden death

Symptoms of syncope

The hallmark sign is evident to anyone around – the patient passes out, faints, suddenly loses consciousness.

The following signs and symptoms may precede a fainting episode:

  • A feeling of heaviness in the legs
  • Blurred vision
  • Confusion
  • Feeling warm or hot
  • Lightheadedness, dizziness, a floating feeling
  • Nausea
  • Sweating
  • Vomiting
  • Yawning.

When a person faints, the following signs may be evident:

  • The individual may be falling over
  • The patient may be slumping
  • The person may be unusually pale
  • There may be a drop in blood pressure
  • There may be a weak pulse.


Even with treatment, not all vasovagal syncope episodes can be avoided. If you feel like you might faint, lie down and lift your legs. This allows gravity to keep blood flowing to your brain. If you can’t lie down, sit down and put your head between your knees until you feel better.

Treating syncope

If the fainting is found to be caused by an underlying health condition, that will need to be treated, which should help prevent syncoptic episodes.

  • Treating neurocardiogenic syncope – in the majority of cases no further treatment is needed. Avoid the triggers, such as long periods standing still, dehydration, and being in hot and stuffy places. This may help prevent future episodes.
  • Injections and blood – if the sight or thought of injections or blood make a person feel faint, they should tell the doctor or nurse beforehand. The health care professional can then make sure the patient is in a safe position (lying down) before any procedure begins.
  • Beta-blockers – this medication is primarily used for the treatment of high blood pressure (hypertension). However, it may help patients whose neurocardiogenic syncope interferes with their quality of life. The side effects of beta-blockers may include fatigue, cold extremities (hands and feet), slow heartbeat (pulse rate), nausea, and diarrhea. Although rare, the following side effects are also possible – erectile dysfunction (impotence, problems either getting or sustaining an erection), nightmares, and sleep disturbances.