A to Z Symptom: Dizziness

What Is Dizziness?

Dizziness refers to feelings of lightheadedness, imbalance, or vertigo (the sensation that one’s surroundings are spinning or moving).

What Causes Dizziness?

Many things can cause dizziness:

Lightheadedness is often the result of a drop in blood pressure (orthostatic hypotension) or not enough blood flow from the heart. Heart problems, stroke, internal bleeding, or shock (when organs don’t get enough blood or oxygen) can also cause it. Lightheadedness also can happen with viruses, low blood sugar, allergies, and dehydration.

A loss of balance or unsteadiness (disequilibrium) can be caused by inner ear problems; joint, muscle, or sensory disorders; neurological conditions; and even taking some medicines.

Vertigo can be caused by:

a peripheral vestibular disorder, when the organs of the inner ear that control balance don’t work properly
a central vestibular disorder, when one or more parts of the brain can’t process information about balance and one’s surroundings
an infection, swelling, irritation (inflammation), or fluid buildup in the inner ear
benign paroxysmal positional vertigo (BPPV), which happens when you quickly change your head position (like tipping it up or down quickly). This isn’t serious.
migraines