Lightheadedness

Lightheadedness is a feeling of faintness, dizziness, or being close to passing out. It can occur alongside vertigo, which affects balance and makes a person feel as though they or their surroundings are spinning. Although lightheadedness and vertigo can feel similar, they have different causes.
Experiencing some episodes of lightheadedness is normal. In most cases, these episodes will pass quickly, especially if a person sits or lies down to rest.
In this article, learn about the common causes of lightheadedness. We also cover possible underlying medical conditions and treatment options.

The most common cause of lightheadedness is orthostatic hypotension, which is a sudden drop in blood pressure when a person stands up.
Positional changes, especially quick ones, divert blood flow temporarily from the brain to the body. It is more likely that this will result in lightheadedness when a person is dehydrated or ill.
The feeling usually passes quickly, especially if a person sits down again.

Other common causes of lightheadedness include:

  • allergies
  • illnesses, such as the cold or flu
  • altitude sickness
  • hyperventilating
  • anxiety
  • stress
  • dehydration
  • prolonged exposure to hot weather
  • low blood sugar
  • alcohol, tobacco, or drug use
  • certain medications

Sometimes, lightheadedness may have a more severe underlying cause, such as:

  • arrhythmia
  • heart attack
  • stroke
  • shock
  • inner ear disorders
  • internal bleeding
  • blood loss
  • neurological conditions, such as Parkinson’s disease and multiple sclerosis
  • anemia
  • conditions that affect blood flow
  • head injuries
  • eating disorders

If lightheadedness is due to a more serious underlying condition, a person will usually experience additional symptoms.