Dizziness is a sensation of spatial disorientation that often leads to a loss of balance and/or a feeling that “the room is spinning.” People use the term to describe any number of sensations, including feeling lightheaded, unsteady and woozy.

Dizziness is usually caused by lack of blood flow to the brain. However, in some cases, dizzy feelings can be the result of certain brain conditions.

Dizziness also may be accompanied by the any of the following symptoms:

Dizziness usually occurs while standing up or walking  and the feeling may be lessened by lying or sitting down. Dizziness is one of the most common reasons for physician visits among older adults. This may be because aging increases the risk of developing conditions that cause dizziness.

In general, physicians recognize four disorders that are often categorized under the term dizziness. They include:

• Vertigo. The illusion of motion, as if the patient or the room is moving or spinning.
  
  
• Nonspecific dizziness. Giddiness, lightheadedness or faint dizziness.
  
  
• Disequilibrium. A sense of imbalance that occurs while walking.
  
  
• Presyncope. Near-fainting, often described by patients as almost blacking out or almost fainting.

Each of these disorders may be the result of a different underlying condition, ranging from inner ear problems to psychiatric disorders to cardiovascular causes. Cardiovascular causes may include:

• Cardiovascular disease (e.g., coronary artery disease or valvular heart disease).
  
  
• Abnormal heart rhythm (arrhythmia). This may involve problems in the communication between the upper and lower chambers of the heart such as heart block or disorders in the heart’s electrical system (Brugada syndrome).
  
  
• Heart attack. Dizziness, shortness of breath and abdominal pain, for example, may be possible signs of a heart attack, even if classical chest pain is not present.
  
  
• Pulmonary hypertension.
  
  
• High blood pressure (hypertension).
  
  
• Low blood pressure (hypotension) or rapid fall in blood pressure.
  
  
• Stroke or transient ischemic attack (called a TIA or mini-stroke). Dizziness is more commonly a symptom of stroke in men than in women.
  
  
• Cardiomyopathy (a type of heart disease in which the heart muscle is abnormally enlarged, thickened and/or stiffened).

However, not all serious causes of dizziness are related to the heart. Non-cardiovascular causes may include:

• Inner ear (vestibular) disorders
  
  
• Anxiety disorders
  
  
• Heat stroke
  
  
• Hyperventilation
  
  
• Hypoglycemia, low blood sugar levels (which, in diabetes, can also be a sign of poor glucose control)
  
  
• Panic attacks
  
  
• Mental illness
  
  
• Brain disease (e.g., a brain tumor)
  
  
• Metabolic disorder
  
  
• Multiple sensory deficits such as failing vision and nerve damage (often seen in older people)
  
  
• Anxiety disorders
  

It is important to note that a brief, isolated dizzy spell may not have significant clinical meaning. These brief spells may be due to standing up too quickly, the use of certain stimulants (e.g., caffeine, nicotine or certain recreational drugs), certain prescription medications (e.g., antihypertensives, vasodilators, birth control pills, hormone replacement therapy) or new prescription eyeglasses. High protein/low carbohydrate diets can cause dizziness due to a quick loss of body fluids.