• Dizziness may result from a disorder that affects any of the many body parts involved in balance (such as the inner ear and eyes) or from certain drugs.
• The person's description of the problem and the results of a physical examination may suggest a cause, which may lead to additional tests.
• Treatment depends on the cause and may include treatment to relieve accompanying symptoms.

Dizziness accounts for about 5 to 6% of visits to the doctor. It may occur at any age but becomes more common as people age. It affects about 40% of people older than 40 at some time. At any age, dizziness can cause problems, particularly when doing an exacting or a dangerous task, such as driving or operating heavy machinery. People who have dizziness that persists or interferes with daily activities should see a doctor.

Doctors usually classify dizziness as

• Faintness or light-headedness
• Loss of balance
• Vertigo
• A mixture of these types
• None of these types

Dizziness may be temporary or chronic. Dizziness is considered chronic if it lasts more than a month. Chronic dizziness is more common among older people. Chronic dizziness is often difficult to classify because it often involves more than one cause and because it seems different at different times—for example, like light-headedness one time and like vertigo the next.

Did You Know... About 95% of the time, dizziness, even if incapacitating, does not result from a serious disorder. In older people, dizziness often does not have a single, obvious cause.

Causes

Although dizziness may be disturbing and even incapacitating, only about 5% of cases result from a serious disorder. Dizziness has many causes because many body parts work together to maintain balance. They include the inner ear, the eyes (which provide visual cues needed to maintain balance), muscles and joints, the brain (mainly the brain stem and cerebellum), and the nerves that connect all of the parts.

Each type of dizziness tends to have characteristic causes. For example, faintness and light-headedness may result from a sudden fall in blood pressure (see Low Blood Pressure: Introduction) or from other disorders that result in an inadequate blood supply to the brain. In these disorders, the heart may be unable to pump enough to the brain, or the arteries to the brain may be blocked or narrowed.

Loss of balance may result from vision disturbances because the body depends on visual cues to maintain balance. Loss of balance may also result from musculoskeletal disorders, which cause muscle weakness and thus interfere with walking. Other causes include use of certain drugs (such as anticonvulsants and sedatives) and disorders of the inner ear.

Classifying Dizziness Type Description Some Possible Causes Faintness The person feels about to black out when upright. The blood pressure drops on standing (orthostatic hypotension) Dehydration Severe blood loss Blocked outflow from the heart (aortic valve stenosis) Abnormal heart rhythms Overmedicated (especially with drugs used for blood pressure control) An autonomic nervous system disorder (diabetic autonomic neuropathy, multi-system atrophy) Loss of balance The person feels unsteady and about to fall even though muscle strength is normal Inner ear disorders (vertigo) Cerebellar disorders (ataxia due to stroke, chronic alcoholism) Basal ganglia disorders (Parkinson's disease, Lewy body dementia, progressive supranuclear palsy) Loss of position sense in the legs (neuropathy or spinal cord disease) Visual disturbances (caused by new glasses, double vision, cataract surgery) Overmedicated with sedatives, anticonvulsants, or other drugs Intoxicated with alcohol Vertigo The person or the person's surroundings seem to be moving or spinning Benign paroxysmal positional vertigo (BPPV) Vestibular neuritis Meniere's disease Middle ear infections Migraine Motion sickness Reduced blood supply to the brain stem and cerebellum (vertebrobasilar insufficiency), as occurs during a stroke or transient ischemic attack (TIA) Multiple sclerosis Drugs toxic to the inner ear (aminoglycoside antibiotics, aspirin, chloroquine, cisplatin [a chemotherapy drug], furosemide [a diuretic], and quinine) Vaguely “lightheaded” Giddy, detached from the world or alternatively caught in a panic attack Abnormally rapid, deep breathing (hyperventilation with a panic attack) Anxiety disorders, Depression with a feeling of disassociation from the world

Diagnosis

Before dizziness can be treated, doctors must determine its nature and its cause. Doctors ask the person to describe in detail the sensations felt: whether the feeling during the episode was faintness, light-headedness, loss of balance, spinning or movement of self or the surroundings (vertigo), or another sensation. The person is asked when the dizziness began, how long it lasted, what triggered or relieved it, and what other symptoms—headaches, deafness, noise in the ears (tinnitus), impaired vision, weakness, or difficulty walking—were present. Such details help pinpoint the nature of the dizziness and may suggest a cause.

One of a doctor's chief aims when performing the physical examination is to reproduce (provoke) the symptoms. A drop in blood pressure on standing up (orthostatic hypotension) is one of the most common causes of dizziness. Therefore, doctors try to provoke the fall in blood pressure by changing the person's position and seeing whether the symptoms develop when the blood pressure changes. Doctors measure blood pressure and pulse after the person has been lying down for 5 to 10 minutes, then after sitting, and again after standing up. A tilt table (see Symptoms and Diagnosis of Heart and Blood Vessel Disorders: Tilt Table Testing) enables the doctor to perform the test more rigorously. Changes in blood pressure may be caused by dehydration, so doctors look for signs of dehydration and order laboratory tests.

The person may be asked to perform a Valsalva maneuver (breathing out vigorously against a closed mouth as if straining at stool). Such a maneuver temporarily slows the heart rate, which may reproduce the dizziness. Electrocardiography (ECG), Holter monitoring for heart rhythm abnormalities, echocardiography, and exercise stress testing may also be done to evaluate heart function.

Several tests can be used to evaluate balance and gait (see Diagnosis of Brain, Spinal Cord, and Nerve Disorders: Coordination, Balance, and Gait), such as the Romberg test. Another test of balance has the person walking a straight line with one foot behind the other.

Vision tests are done, and the eyes may be checked for abnormal movements (such as nystagmus—see Dizziness and Vertigo: Physical Examination). If doctors suspect vertigo, they perform special tests to provoke the symptoms (see Dizziness and Vertigo: Diagnosis). In addition, hearing tests can be used to detect inner ear disorders that affect both balance and hearing.

Additional diagnostic procedures may include computed tomography (CT) and magnetic resonance imaging (MRI) of the head. These procedures are especially useful if doctors suspect that the blood supply to the brain is inadequate and causing stroke-like symptoms. In addition, CT angiography, magnetic resonance angiography (MRA), or cerebral angiography (also called catheter angiography because a catheter is introduced into an artery) may show whether arteries to the brain are narrowed or blocked. CT angiography and MRA are not invasive and are generally preferred to cerebral angiography.

When other diagnostic possibilities appear unlikely or no obvious cause of dizziness is found, the doctor may inquire about a possible psychologic cause. Several tests can help doctors identify depression, somatization disorders, and other psychologic problems that may predispose the person to giddiness or a feeling of disassociation from the world. If no cause is identified, doctors reexamine the person periodically.

Treatment

Specific treatment depends on the cause identified. Getting sufficient fluids often improves orthostatic hypotension resulting from dehydration. Drugs (such as mineralocorticoids and midodrine) may be needed for people with orthostatic hypotension due to dysfunction of the autonomic nervous system. If the cause of dizziness is a drug, the drug is stopped or the dose reduced. Benign paroxysmal positional vertigo (BPPV) can often be relieved by a simple head-turning maneuver (Epley maneuver) done in the doctor's office (see Dizziness and Vertigo: The Epley Maneuver: A Simple Cure for a Common Cause of Vertigo). If doctors suspect the symptoms are stroke-like, then risk factors are treated, such as giving antiplatelet drugs and possibly bypassing or placing a stent in a blocked artery.

Regardless of whether a cause is identified, drugs may be given to relieve accompanying symptoms (such as nausea) or to prevent blood pressure from falling.

Spotlight on Aging As people age, some of the body parts involved in balance function less well. For example, seeing in dim light becomes more difficult, and structures in the inner ear deteriorate. The mechanisms that control blood pressure become less responsive to changes in the body's need for blood. As a result, blood pressure may fall when a person stands (causing orthostatic hypotension—see Low Blood Pressure: Orthostatic Hypotension) or after a meal is eaten (causing postprandial hypotension—see Low Blood Pressure: Postprandial Hypotension), and the person feels faint. Usually, dizziness does not result from age-related changes alone. It is more likely to occur if a person has a disorder or takes a drug that contributes to dizziness. Disorders that can contribute to dizziness (such as heart disorders and stroke) are more common among older people. So is pain from arthritis that affects the lower back, hips, and knees and limits walking. Older people may feel or fear being abandoned just when they are also losing their independence. Depression may cause apathy and a feeling of disassociation from the world. Also, people who are depressed often lose interest in many activities. Inactivity from any cause can accelerate osteoporosis and muscle weakness from disuse. People may feel weak, unsteady, faint, and anxious when attempting to walk, fearing falls and hip fracture. Older people are more likely to take drugs that can contribute to dizziness. These drugs include those used to treat high blood pressure, chest pain (angina), heart failure, seizures, or anxiety, as well as certain antibiotics, antihistamines, and sleep aids. Some antihistamines (such as meclizine) are used to treat vertigo. They are more likely to have side effects in older people. Thus, older people should avoid taking these drugs whenever possible. The same can be said for over-the-counter antihistamines and sleep aids. Two disorders of the inner ear are common causes of dizziness in older people: benign paroxysmal positional vertigo (see Dizziness and Vertigo: Benign Paroxysmal Positional Vertigo (Benign Positional Vertigo)) and Meniere's disease (see Middle and Inner Ear Disorders: Meniere's Disease). In older people, chronic dizziness increases the risk of falling and fractures and decreases the ability to do daily activities. Chronic dizziness often has many causes and is thus hard to treat. When an examination does not suggest a single cause, doctors try to correct as many factors that can contribute to dizziness as possible. If dizziness persists despite treatment, people can learn strategies to help them function better, such as the following: Avoiding movements that, for them, trigger dizziness, such as looking up or bending down Storing items at levels that are easy to reach Getting up slowly after sitting or lying down Clenching their hands and flexing their feet before standing Learning exercises that combine eye, head, and body movements to help prevent dizziness Physical therapy and exercises to strengthen muscles and maintain independent gait as long as possible

Last full review/revision October 2007