Dizziness
Dizziness refers to an impairment in spatial perception and stability.[1] The term is somewhat imprecise.[2] It can be used to mean vertigo, presyncope, disequilibrium,[3] or a non-specific feeling such as giddiness or foolishness.[4]
One can induce dizziness by engaging in disorientating activities such as spinning.
- Vertigo is a specific medical term used to describe the sensation of spinning or having one's surroundings spin about them. Many people find vertigo very disturbing and often report associated nausea and vomiting. It represents about 25% of cases of occurrences of dizziness.[5]
- Disequilibrium is the sensation of being off balance, and is most often characterized by frequent falls in a specific direction. This condition is not often associated with nausea or vomiting.
- Presyncope is lightheadedness, muscular weakness and feeling faint as opposed to a syncope, which is actually fainting.
- Non-specific dizziness is often psychiatric in origin. It is a diagnosis of exclusion and can sometimes be brought about by hyperventilation.[4]
A stroke is the cause of isolated dizziness in 0.7% of people who present to the emergency room.[5]
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Classification
Dizziness is broken down into 4 main subtypes: vertigo (~50%), disequilibrium (less than ~15%), presyncope (less than ~15%) and lightheadedness (~10%).[6]
Differential diagnosis
Many conditions are associated with dizziness. However, the most common subcategories can be broken down as follows: 40% peripheral vestibular dysfunction, 10% central nervous system lesion, 15% psychiatric disorder, 25% presyncope/dysequilibrium, and 10% nonspecific dizziness.[7] The medical conditions that often have dizziness as a symptom include:[7][8][9][10]
- Benign paroxysmal positional vertigo
- Meniere's disease
- Vestibular neuronitis
- Labyrinthitis
- Otitis media
- Acoustic neuroma
- Chronic motion sickness
- Ramsay Hunt syndrome
- Migraine
- Multiple sclerosis
- pregnancy
- low blood pressure (hypotension)
- low blood oxygen content (hypoxemia)
- iron deficiency (anemia)
- low blood sugar (hypoglycemia)
- hormonal changes (e.g., thyroid disease, menstruation, pregnancy)
- panic disorder
- hyperventilation
- anxiety
- depression
- age-diminished visual, balance, and perception of spatial orientation abilities
Mechanism
Many conditions cause dizziness because multiple parts of the body are required for maintaining balance including the inner ear, eyes, muscles, skeleton, and the nervous system.[9]
Common physiological causes of dizziness include:
- inadequate blood supply to the brain due to:
- loss or distortion of vision or visual cues[9]
- disorders of the inner ear[9]
- distortion of brain/nervous function by medications such as anticonvulsants and sedatives[9]
Epidemiology
About 20–30% of the population report to have experienced dizziness at some point in the previous year.[5]
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Definition
By Mayo Clinic staffDizziness is a term used to describe everything from feeling faint or lightheaded to feeling weak or unsteady. Dizziness that creates the sense that you or your surroundings are spinning or moving is called vertigo.
Dizziness is one of the most common reasons adults visit their doctors — right up there with chest pain and fatigue. Although frequent dizzy spells or constant dizziness can keep you from doing much of anything, dizziness rarely signals a serious, life-threatening condition. Treatment of dizziness depends on the cause and your symptoms, but is usually effective.
Symptoms
By Mayo Clinic staffDizziness can usually be more specifically described as one of the following sensations:
- Vertigo — the false sense of motion or spinning
- Lightheadedness or the feeling of near fainting (presyncope)
- Loss of balance (disequilibrium)
- Other sensations such as floating, swimming or heavy-headedness
A number of underlying health conditions can cause these problems. Some of these conditions disrupt or confuse the signals your brain receives from one or more of your sensory systems, including your:
- Eyes, which help you determine where your body is in space and how it's moving
- Sensory nerves, which send messages to your brain about body movements and positions
- Inner ear, which houses sensors that help detect gravity and back-and-forth motion
When to see a doctor
See your doctor if you experience any unexplained, recurrent or severe dizziness.
Call 911 or go to the emergency room if you experience dizziness or vertigo along with any of the following:
- Significant head injury
- A new, different or severe headache
- A fever higher than 101 F (38.3 C)
- A very stiff neck
- Blurred vision
- Sudden hearing loss
- Speech impairment
- Leg or arm weakness
- Loss of consciousness
- Falling or difficulty walking
- Chest pain or rapid or slow heart rate
Causes
By Mayo Clinic staff
The key sensations that characterize your dizziness — such as vertigo, a feeling of faintness or loss of balance — provide clues for possible causes.
Vertigo
Vertigo usually results from a problem with the nerves and the structures of the balance mechanism in your inner ear (vestibular system), which sense movement and changes in your head position. Sitting up or moving around may make it worse. Sometimes vertigo is severe enough to cause nausea, vomiting and imbalance.
Causes of vertigo may include:
- Benign paroxysmal positional vertigo (BPPV). BPPV causes intense, brief episodes of vertigo immediately following a change in the position of your head, often when you turn over in bed or sit up in the morning. BPPV is the most common cause of vertigo.
- Inflammation in the inner ear. Signs and symptoms of inflammation of your inner ear (acute vestibular neuritis) include the spontaneous onset of intense, constant vertigo that may persist for several days, along with nausea, vomiting and imbalance. It can be incapacitating, requiring bed rest. When associated with sudden hearing loss, this condition is referred to as labyrinthitis. Fortunately, vestibular neuritis generally subsides and clears up on its own.
- Meniere's disease. This disease involves the excessive buildup of fluid in your inner ear. It is an uncommon condition that may affect adults at any age and is characterized by sudden episodes of vertigo lasting 30 minutes to several hours.
- Migrainous vertigo. Migraine is more than a headache disorder. Just as some people experience a visual "aura" with their migraines, others can get vertigo episodes and have other types of dizziness between migraines.
- Acoustic neuroma. An acoustic neuroma (vestibular schwannoma) is a noncancerous (benign) growth on the vestibular nerve, which connects the inner ear to your brain. Symptoms of an acoustic neuroma generally include progressive hearing loss and tinnitus on one side accompanied by dizziness or imbalance.
- Other causes. Rarely, vertigo can be a symptom of a more serious neurological problem such as a stroke, brain hemorrhage or multiple sclerosis. In such cases, other neurological symptoms are usually present, such as double vision, slurred speech, facial weakness or numbness, limb coordination, or severe balance problems.
Feeling of faintness (presyncope)
Presyncope is the medical term for feeling faint and lightheaded without losing consciousness. Sometimes nausea, pale skin and clamminess accompany a feeling of faintness. Causes of presyncope include:
- Drop in blood pressure (orthostatic hypotension). A dramatic drop in your systolic blood pressure — the higher number in your blood pressure reading — may result in lightheadedness or a feeling of faintness. It can occur after sitting up or standing too quickly.
- Inadequate output of blood from the heart. Conditions such as any of the various diseases of the heart muscle (cardiomyopathy), an abnormal heart rhythm (arrhythmia) or a decrease in blood volume may cause inadequate blood flow from your heart.
Loss of balance (disequilibrium)
Disequilibrium is the loss of balance or the feeling of unsteadiness when you walk. Causes may include:
- Inner ear (vestibular) problems. Abnormalities with your inner ear can cause you to feel like you are unsteady while walking, especially in the dark.
- Sensory disorders. Failing vision and nerve damage in your legs (peripheral neuropathy) are common in older adults and may result in difficulty maintaining your balance.
- Joint and muscle problems. Muscle weakness and osteoarthritis — the type of arthritis that involves wear and tear of your joints — can contribute to loss of balance when it involves your weight-bearing joints.
- Neurological conditions. Various neurological disorders can lead to progressive loss of balance, including Parkinson's disease, cerebellar ataxia, normal pressure hydrocephalus and spinal cord disorders.
- Medications. Loss of balance can be a side effect of certain medications, such as anti-seizure drugs, sedatives and tranquilizers.
Other dizzy sensations such as floating, swimming or heavy-headedness
Other "dizzy" sensations that are more difficult to describe may include feeling "spaced out" or having the sensation of spinning inside your head. Some causes include:
- Medications. Blood pressure lowering medications may cause faintness if they lower your blood pressure too much. Many other medications can cause nonspecific feelings of dizziness that resolve when you stop the medication.
- Inner ear disorders. Some inner ear abnormalities can cause persistent, non-vertigo-type dizziness.
- Anxiety disorders. Certain anxiety disorders, such as panic attacks and a fear of leaving home or being in large, open spaces (agoraphobia), may cause dizziness. Sometimes one cause — such as a vestibular disorder — may produce symptoms, but then anxiety causes your dizziness to persist even after your inner ear problem has resolved.
Complications
By Mayo Clinic staffDizziness can increase your risk of falling and injuring yourself. Experiencing dizziness while driving a car or operating heavy machinery can increase the likelihood of an accident. You may also experience long-term consequences if an existing health condition that may be causing your dizziness goes untreated.
Treatment
BPPV. Treatment of BPPV is with canalith repositioning, a simple procedure in which your doctor or physical therapist maneuvers the position of your head. This procedure is usually effective after one or two treatments.Doctors base treatment of dizziness on the cause and your symptoms.
- Inner ear conditions. Balance retraining exercises (vestibular rehabilitation) are used to treat acute vestibular neuronitis or labyrinthitis. These are exercises you learn from a physical therapist or occupational therapist and then do at home. To provide immediate relief of nausea and dizziness, your doctor may prescribe medications such as meclizine (Antivert) and diazepam (Valium) or may recommend dimenhydrinate (Dramamine), available over-the-counter. A short course of corticosteroids may improve your vestibular function.
- Meniere's disease. Treatment of Meniere's disease involves reducing your body's retention of fluids through diuretic use and often dietary changes, such as a low-salt diet. Occasionally, surgery is an option.
- Migrainous vertigo. To combat vertigo associated with a vestibular migraine, your doctor will likely try to help you determine and avoid the triggers for your attacks, focusing on diet, stress, sleep and exercise. Certain medicines may help prevent attacks of migrainous vertigo or make them less uncomfortable by providing relief for nausea and vomiting. You may also learn specific exercises to help make your balance system less sensitive to motion (vestibular rehabilitation).
- Anxiety disorders. Your doctor may suggest medications and psychotherapy, either alone or in combination, to help you deal with your anxiety and manage your dizziness.
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