What's Causing My Dizziness? Causes, Symptoms, Treatment (original) (raw)

Introduction to dizziness (feeling dizzy)

Picture of the symptoms of a balance disorder

Picture of the symptoms of a balance disorder

Dizziness is one of the most common symptoms that will prompt a person to seek medical care.

Lightheadedness is often caused by a decrease in blood supply to the brain, while vertigo may be caused by disturbances of the inner ear and the balance centers of the brain.

It is important that the doctor understand the complaint the person is experiencing, which is the first step to finding a diagnosis and beginning treatment.

What causes dizziness?

While classifying dizziness into lightheadedness and vertigo categories may help understand how the body works, sometimes it is worthwhile to review common reasons why people might complain of dizziness.

Low blood pressure as a cause of dizziness

Dizziness, lightheadedness, and the feeling of passing out are common complaints in people who have low blood pressure. When the blood pressure is too low, not enough oxygen-rich blood is delivered to the brain, and its function can be affected. If the brain's blood supply is decreased too much, the person may pass out (syncope).

Symptoms may worsen when changing position from lying down or sitting to standing up.

In addition to feeling dizzy, associated symptoms may include:

Low blood pressure may be the result of an underlying illness or disease, or it may be a normal physiologic condition.

Some common reasons for low blood pressure include the following:

SLIDESHOW Balance Disorders: Vertigo, Motion Sickness, Labyrinthitis, and More See Slideshow

Postural or orthostatic hypotension as a cause of dizziness

In individuals who are dehydrated or anemic, blood pressure readings may be normal when they are lying flat; however, the lack of fluid is unmasked when they stand up quickly. The lack of blood in the brain may cause dizziness and lightheadedness. This feeling may pass in a few seconds as the body adapts. However, if dehydration or medications (for example, beta-blockers) prevent the body from reacting by constricting blood vessels and increasing the heart rate, the dizziness may persist to the point at which the patient passes out (faints or experiences syncope).

Some diseases are associated with an inability to compensate for changes in body position (autonomic dysfunction). Normally when a person stands, blood vessels contract to increase blood pressure slightly, and the heart rate also increases slightly, to pump blood uphill to the brain against gravity. In autonomic dysfunction, a person may become dizzy when they move from a lying position to sitting or standing up. Examples of these diseases with this syndrome include diabetes, Addison's disease, or Parkinson's disease.

Orthostatic hypotension is a common symptom of Shy-Drager syndrome. Shy-Drager syndrome is a rare disease in which the autonomic nervous system degenerates and cannot provide the routine control mechanisms for the body including heart rate, blood pressure, and bowel and bladder function.

Health News

High blood pressure as a cause of dizziness

High blood pressure, or hypertension, is known as the "silent killer" since it often has no symptoms, even if blood pressure readings are markedly elevated. On occasion, a person may complain of headache, nausea, or dizziness, although the complaints don't necessarily correlate with the degree of blood pressure elevation.

However, if the blood pressure is elevated and the person has symptoms, there is a need to bring the blood pressure under control relatively quickly. The more severe the symptoms, the quicker blood pressure needs to be controlled. For example, if a person is having chest pain or stroke symptoms associated with high blood pressure, the blood pressure needs to be controlled immediately (hypertensive emergency).

Elevated blood pressure without symptoms is not an emergency and, while the blood pressure needs to be brought under control, there is no urgency to do so immediately.

Diabetes as a cause of dizziness

Dizziness is a common complaint in persons with diabetes and may be caused by low blood sugar (hypoglycemia), high blood sugar (hyperglycemia), or autonomic dysfunction (see the previous section).

Subscribe to MedicineNet's General Health Newsletter

By clicking Submit, I agree to the MedicineNet's Terms & Conditions & Privacy Policy and understand that I may opt out of MedicineNet's subscriptions at any time.

Endocrine diseases that cause dizziness

Hyperventilation as a cause of dizziness

While the body may use hyperventilation or rapid breathing to help with acid-base balance, it may also occur as a response to an emotionally stressful situation. In hyperventilation syndrome, rapid breathing eliminates some of the body's carbon dioxide, leading to a tingling sensation in the hands and feet, and around the mouth. Dizziness and lightheadedness are associated symptoms. The symptoms may increase the perceived emotional stress and cause even more hyperventilation. In severe hyperventilation, carbon dioxide levels drop enough to cause carpopedal spasm, in which the hands and feet become claw-like and difficult to move. Symptoms of hyperventilation resolve relatively quickly once the breathing rate returns to normal.

Hyperventilation is not always an emotional response. People with asthma, exacerbations of COPD, congestive heart failure, and pneumonia also may breathe quickly to help maintain oxygen levels in the bloodstream. Hyperventilation is also present whenever the body becomes acidotic (for example, diabetic ketoacidosis); rapid breathing is one correction method that the body uses to regulate its acid-base balance.

Heart conditions that cause dizziness

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.

Vasovagal syncope as a cause of dizziness

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 toward the brain. Without blood flow, the brain turns off. In Victorian England, young ladies' sensibilities were easily offended causing a vasovagal episode called a swoon.

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

Fainting is not normal. If a person is unconscious, activate the emergency medical system (call 911 if available), and seek medical care.

Dizziness and vertigo

Picture of the structures of the ear

Picture of the structures of the ear

Vertigo is often described as feeling dizzy, or as a sensation of spinning. A person may specifically mention that the room seems to be spinning around them. Sometimes the complaint is loss of balance or loss of equilibrium. This often occurs because of irritation in the inner ear (the part of the ear that involves balance, not hearing).

The inner ear has two parts that help the body determine its position in space relative to gravity; 1) the semicircular canals and 2) the vestibule.

Three semicircular canals are aligned at right angles to each other. These canals are fluid-filled and lined with a nerve-rich, crystal-encrusted membrane that transmits information to the cerebellum (the part of the brain that controls balance and coordination). The cerebellum collects information from the eyes (visual stimuli) and the nerve endings in muscles associated with proprioception (the perception of movement), to assist the brain in assessing where the body is in relationship to gravity every time one part of it moves.

Normally, when the head moves, fluid in the semicircular canals shifts, and that information is relayed to the brain. When the head stops moving, the fluid stops as well, and that information is relayed to the brain.

In some cases, there may be a short delay in the transmission of this information to the brain. For example, when a person rides on a merry-go-round or spins quickly around in circles, the fluid in the canals develops momentum and though the body stops spinning, the fluid in the semicircular canals may continue to move. This causes vertigo, or a sensation of spinning, and may cause the person to fall or stumble. It also may be associated with vomiting. While kids try to provoke these symptoms in play, they can be debilitating for an adult.

What are the symptoms experienced from dizziness?

When should I call the doctor for dizziness?

Dizziness is a common complaint and often has resolved by the time the patient arrives to see a health care professional.

Usually, there is no rush to seek care; however, while the complaint of dizziness is not often an emergency, seek care immediately if it is accompanied by any of the following:

How is dizziness diagnosed?

The diagnosis of dizziness begins with the health care professional deciding whether the complaint of dizziness refers to lightheadedness or vertigo. Further diagnosis continues once this distinction is made.

The key to the diagnosis of dizziness is a thorough history and physical examination. Often the diagnosis is made by listening to the patient's story. The health care professional may ask about triggers that cause and relieve the symptoms of dizziness.

A review of systems is a series of questions that review the patient's body functions. The doctor may ask questions about associated symptoms including fever, vomiting, diarrhea, chest pain, shortness of breath, palpitations, or abnormal bleeding.

The doctor may review the past medical history, and this includes reviewing medications the patient is currently taking.

The doctor may do a thorough physical examination that may include:

How is vertigo diagnosed?

The diagnosis of vertigo is most often made based upon history and clinical presentation. If the patient is experiencing a spinning sensation that worsens by a change in position and lessens by lying still, the health care professional can confirm the cause of dizziness as vertigo if there are appropriate findings on physical examination.

The doctor may take a further history to make certain that the symptom of vertigo is isolated to an inner ear condition and not due to a problem in the brain (for example, a stroke).

Neurological examination

A physical examination will focus on the neurologic examination and may involve looking at eye movements. With vertigo, nystagmus may be present. Nystagmus is an involuntary movement of the eyes, slow and smooth in one direction with fast twitches in the other. The eyes attempt to compensate for the abnormal signals created in the inner ear. The patient may be asked to lay flat or sit upright to uncover the presence of nystagmus.

The doctor may test the patient's hearing to assess potential hearing loss. This may be seen in Meniere's disease or with an acoustic neuroma, but not necessarily with labyrinthitis or benign positional vertigo.

The rest of the neurologic examination may be done to look for one-sided weakness, loss of coordination, or loss of balance as potential signs of stroke.

Evaluation for BPPV or labyrinthitis is often complete at this point, although depending upon the health care professional's concerns, further testing may be indicated. Patients may be referred to a physical therapist specially trained in vestibular therapy for diagnosis confirmation and symptom relief.

If there is confusion as to the potential cause of vertigo, imaging of the brain may be needed. Magnetic resonance imaging (MRI) may be indicated since this test evaluates the cerebellum more accurately. Computerized tomography (CT scan) may be used in an emergency to look for bleeding in the brain.

How is dizziness and vertigo treated?

Dizziness treatment

Dizziness is a symptom, not a disease, and treatment will be directed to the underlying cause. For example, dizziness or lightheadedness due to dehydration from gastroenteritis may require intravenous fluids and medications to stop the vomiting and diarrhea, while dizziness or lightheadedness from a heart rhythm condition may require admission to the hospital and specialized testing and treatment.

Vertigo treatment

References

Kasper, D.L., et al., eds. Harrison's Principles of Internal Medicine, 19th Ed. United States: McGraw-Hill Education.