1. Balance Disorders Slideshow
2. Take the Vertigo Quiz
3. Tinnitus Slideshow: Why Are My Ears Ringing?

Medical Author:

Benjamin Wedro, MD, FACEP, FAAEM

Benjamin Wedro, MD, FACEP, FAAEM

Dr. Ben Wedro practices emergency medicine at Gundersen Clinic, a regional trauma center in La Crosse, Wisconsin. His background includes undergraduate and medical studies at the University of Alberta, a Family Practice internship at Queen's University in Kingston, Ontario and residency training in Emergency Medicine at the University of Oklahoma Health Sciences Center.

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Medical Editor:

Melissa Conrad Stöppler, MD

Melissa Conrad Stöppler, MD

Melissa Conrad Stöppler, MD, is a U.S. board-certified Anatomic Pathologist with subspecialty training in the fields of Experimental and Molecular Pathology. Dr. Stöppler's educational background includes a BA with Highest Distinction from the University of Virginia and an MD from the University of North Carolina. She completed residency training in Anatomic Pathology at Georgetown University followed by subspecialty fellowship training in molecular diagnostics and experimental pathology.

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In this Article

• Introduction to dizziness (feeling dizzy)
• What are some common causes of dizziness?
• Low blood pressure
• Postural or orthostatic hypotension
• High blood pressure
• Diabetes
• Endocrine diseases
• Hyperventilation
• Heart conditions
• Vasovagal syncope
• Dizziness and vertigo
• What are the symptoms experienced when a person feels dizzy?
• When should I call the doctor for dizziness?
• How is dizziness diagnosed?
• How is dizziness/vertigo diagnosed?
• How is dizziness treated?
• Dizziness At A Glance
• Patient Comments: Dizziness - Diagnosis
• Patient Comments: Dizziness - Causes
• Patient Comments: Dizziness - Standing Up
• Patient Comments: Dizziness - Treatment
• Dizziness (Dizzy) Index

The heart is an electrical pump and for it to work, the electrical conduction system must be operating properly to stimulate the heart muscle to squeeze in a coordinated fashion and pump blood to the body. The heart muscle itself must be strong enough to pump blood, and the valves in the heart must work properly to allow blood to flow in the direction intended during contraction.

• Conduction disturbances: Electrical conduction disturbances may make the heart beat too quickly (tachycardia) or too slowly (bradycardia), and either of these situations may result in an inadequate blood supply to the brain, causing dizziness or lightheadedness.
  
  
• Cardiomyopathy: Dizziness is also a symptom of cardiomyopathy (cardio=heart +myo=muscle + pathy= disease), a disease of the heart muscle, resulting in muscle that doesn't beat properly. Most commonly the weakness is due to atherosclerotic heart disease or ischemic cardiomyopathy (ischemic=decreased blood supply), in which the heart muscle itself doesn't get enough blood supply to work properly. Other cardiomyopathies may be due to diabetes, alcohol use, and viral infections.

Vasovagal syncope is a common cause of dizziness, lightheadedness, and fainting. The vagus nerve is overstimulated and causes the body's blood vessels to dilate and the heart to slow down. This anti-adrenaline effect decreases the ability of the heart to pump blood upward to the brain. Without blood flow, the brain turns off. In Victorian England, when this happened because young ladies' sensibilities were easily offended, this was called a swoon.

Some people faint at the sight of blood. Some parents faint when their child gets immunized. Many types of emotional and physical stressors can overstimulate stimulate the vagus nerve, thus causing dizziness, lightheadedness, and at times fainting (passing out).

Fainting is not normal. If a person is unconscious, the emergency medical system should be activated (call 911 if available), and medical care should be sought.