Dizziness is one of the most frequent reasons people seek out a doctor, and it can be caused by a wide array of illnesses and conditions. If you are experiencing dizziness, a thorough medical evaluation is important.
What is dizziness?
Dizziness is a disruption in your sense of balance, and it can come in many different forms—as a sensation of unsteadiness, spinning or general disorientation in relation to your surroundings. You may feel lightheaded, nauseated, woozy or like you might faint.
The body's balance system
To understand how dizziness occurs, it helps to know how the balance organ and vestibular system work:
The balance organ
Deep within your ears, there are three tiny semicircular canals filled with fluid and crystals, known as endolymph and otoliths. The crystals float and move around in the fluid in response to your body's angular position. Two other sac-like structures, the utricle and saccule, detect vertical and horizontal movements. Together, these structures are called your balance organ, because they help your body seamlessly detect up from down, left from right, as well as forward and backward motion.
The vestibular system
The balance organ coordinates with your eyesight and the muscles and joints in your body to provide you with a sense of balance and orientation in your environment. This is medically known as the vestibular system.
Common dizziness symptoms
Dizziness is what happens when there is a deficit in any of the vestibular senses, or the brain centers that tie them all together. Dizziness is not a disease in itself, but a symptom of a larger problem rather than a disease. Many different conditions can cause dizziness, and it's also a common drug side effect. Even ordinary things—like being on long, hilly car ride—can trigger dizziness in the form of motion sickness.
There are four main categories of dizziness, according to the American Academy of Family Physicians:
Inner ear causes of dizziness
Some of the most common causes of dizziness arise from problems in your inner ear. A disturbance in the blood circulation or fluid pressure in the inner ear can trigger dizziness and tinnitus. For example, a bad cold can swell your inner ears and lead to bouts of dizziness. You might also experience dizziness if there is pressure on the nerves responsible for delivering balance information to your brain.
Hearing loss and dizziness: What does it mean?
There are many health conditions that can affect the inner ear and cause both dizziness and hearing loss, including severe allergies, bacterial or viral infections of the inner ear, medication side effects and some circulatory conditions. If you experience sudden dizziness and hearing loss, see a doctor right away.
Ringing in the ears and dizziness
Many disorders that affect the inner ear can potentially lead to ringing in the ears (tinnitus) and dizziness, especially Meniere’s disease.
Benign paroxysmal positional vertigo (BPPV) typically causes dizziness but no other symptoms.
Dizziness caused by the inner ear may feel like a whirling or spinning sensation (vertigo), unsteadiness or lightheadedness and it may be constant or intermittent. It may be aggravated by certain head motions or sudden positional changes. Although nausea and vomiting may occur, people do not typically lose consciousness as a result of inner ear dizziness.
Other causes of dizziness
There are many other causes of dizziness that are not related to the function of the inner ear. They are generally sorted into two categories: central dizziness and visual dizziness.
If the brain is not able to coordinate the inputs from the three parts of the vestibular system, there is central dizziness. Central dizziness may be caused by migraines, tumors, infections and degenerative diseases like multiple sclerosis. If you've ever felt the room spinning after a night of too many alcoholic drinks, than you know what central dizziness feels like.
Visual dizziness can occur if the eye muscles are imbalanced or there are errors of refraction, such as when you borrow a pair of eyeglasses from a friend with a different prescription. Other causes of visual dizziness include intermittent inability to focus the eyes, difficulty reading or intermittent blurring of vision.
Very rarely, dizzy symptoms may be caused by muscle or joint issues, such as unsteadiness due to muscular dystrophy. General health problems, such as diabetes, thyroid deficiency, vitamin deficiency, anemia and arterial blockage can cause dizziness as well.
How your body 'compensates'
When one part of your vestibular system is afflicted, the other parts can usually compensate for the deficit. Once the system is under too much stress, though, that compensation may fall short. For example, if you must take an ototoxic drug that destroys the balance organs of the inner ear, you can still stay quite balanced as long as your eyes are open. However, when you are asked to close your eyes, you may find it quite difficult to stay standing upright.
To figure out what's causing dizziness, a medical provider must take a thorough medical history and exam.
A very common cause of dizziness that is often overlooked is the interaction of one or multiple prescription and/or over-the-counter medications. If you have recently changed or added a prescription to your daily routine, be sure to ask your physician about the possibility of dizziness as a side effect. The same is true of alcohol and caffeine–both can interact with your medications.
Tests for dizziness
There are a wide array of tests a doctor may use to evaluate dizziness, and they may be performed by a primary care doctor, a physical therapist, cardiologist or neurologist.
In some cases, especially if you also experience hearing loss, you may undergo a hearing test. The cochlea, your hearing organ, is contained within the same bony structure as your balance organ. A behavioral hearing test in a sound booth may be followed by an Auditory Brainstem Response (ABR) test. An ABR test non-invasively records brainstem responses to sound stimuli. The brain waves are collected while you rest comfortably with your eyes closed. The presence or absence of hearing loss or auditory brainstem anomalies will provide clues to the physician about the cause of your symptoms.
Another common test for balance is VNG, or videonystagmography. Usually performed by an ENT physician or an audiologist, a VNG test uses video cameras to record eye movements while a patient tracks a visual stimulus, is moved into different positions and while the ear canals are stimulated with warm and cool air or water. This test gives a broad picture of whether the underlying issue is related to the inner ear or not.
Treatments for dizziness
Appropriate treatment for dizzy symptoms will depend on the underlying cause, so it is important that you see a physician. Your doctor might prescribe something to help the dizzy symptoms temporarily, for example.
When the cause of the dizziness is determined and treated, the symptom will often go away. For BPPV, dizziness can be treated by a simple head positioning maneuver.
Many other disorders can be treated with medication, surgery, diet, lifestyle changes or some combination of these. There are also physical therapists who specialize in vestibular rehabilitation, which is a treatment for balance disorders that gradually retrains the brain to compensate for lost sensory input from the balance system.
When to get help
If you experience any dizziness symptoms that don't go away, you should talk to your physician or a hearing care provider so the underlying cause can be determined and the problem remediated.